Drug Half-Life, Steady State, and Recommended Sample Collection Time

This Topic Brief provides the drug half-life and time to steady state for many therapeutic drugs. It also provides guidance on how to use this information when monitoring therapeutic drugs.

Topic Brief

Therapeutic Drug Monitoring

Drug Half-Life, Steady State, and Recommended Specimen Collection Time

Therapeutic drug monitoring (TDM) is commonly used to determine whether measured drug levels are within the therapeutic range.^1,2 The therapeutic range is the concentration range over which, for most patients, the probability of a beneficial clinical response is high and the probability of toxic effects is low. TDM is particularly useful for monitoring drugs that are used long-term and have a narrow therapeutic range.^1,2 TDM is also useful to help detect and monitor drug-drug interactions and help identify inadequate patient adherence to prescribed therapy as a cause of poor treatment response.^1,2

After administering a drug at regular intervals and fixed dose, the most clinically useful time to collect a specimen for TDM is at steady state. At a steady state, the drug has reached an equilibrium between equal rates of adsorption and elimination.¹ The time required to reach steady state depends on the drug’s elimination half-life, which is determined by the drug’s metabolism and excretion rates.

The number of half-lives to reach steady state depends on the

Kinetics of elimination: most drugs follow first-order kinetics with constant proportion of drug eliminated dependent on plasma concentration.
Compartment model of distribution: most drugs follow a 1-compartment distribution model and are rapidly and evenly distributed throughout the body.^1,3

Under these conditions, steady state concentrations of drug are usually reached within 5 half-lives assuming that therapy was not initiated with a high loading dose for an immediate therapeutic response.⁴

Steady state concentrations of drugs may deviate from 5 half-lives if they

Follow non–first-order kinetics⁵ (eg, phenytoin, ethanol, and aspirin [salicylates at high concentration] follow zero-order [saturation] kinetics; elimination is independent of plasma concentration; thus, increases in dose may not correspond to increases in plasma concentrations⁶).
Have multicompartment distribution models; the drug initially enters plasma and then distributes at different rates between plasma and tissues (eg, aminoglycoside antibacterials: gentamicin, amikacin, and tobramycin⁷ [2-compartment] and antiarrhythmic amiodarone [multiple compartments]).³
Undergo extensive first-pass metabolism in the liver³

Except in medical emergencies, a monitored drug should be allowed to reach a new steady state following a dosage change, the addition or discontinuation of a co-administered drug that affects the first drug’s metabolism, or both.¹ Similarly, a period of at least 5 half-lives must elapse to almost completely eliminate a discontinued drug that had reached steady state.¹

Once steady state has been reached, drug concentrations in peak and/or trough serum specimens may be determined. Peak specimens are typically collected 2 to 3 hours after an oral dose²; 30 to 60 minutes after an intravenous dose²; 2 to 4 hours after an intramuscular dose²; or 1 to 1.5 hours after an intranasal dose.^8,9 Trough specimens are collected just before administration of the next scheduled dose. TDM of aminoglycoside antibiotics, such as gentamicin, tobramycin, and amikacin, requires determination of both peak and trough concentrations for multiple daily dosing regimens.^3,7 For most other drugs, only trough concentrations are measured.²

The Table contains, unless otherwise specified, estimates of drug half-life and steady state specimen collection times, and test codes for drugs commonly prescribed as immediate-release formulations and excluding time-release and long-acting formulations. The pharmacokinetics of each drug may vary with patient age, sex, weight, clinical status, and the presence of other drugs.

Test codes for blood-based drug screening panels are provided for use when (a) assays for the individual drugs are unavailable to determine half-life and steady state or (b) individual drug assay test results and/or clinical presentation suggests nonadherence to prescribed therapy (eg, drug test result is "not detected" or clinical presentation suggests use of unprescribed drugs).

All test codes are linked to the Quest Diagnostics: Test Directory for more information. Parameters provided in the table provide generalized guidance and are not meant to replace patient assessment and clinical judgment.

Table. Drug Half-life and Time to Steady State^a [A-F] [G-N] [O-Z]

Drug name	Half-life		Time to steady state		Test code
Acetaminophen	2-3 hours¹⁰	adult	10-20 hours¹⁰		201
	1-3 hours¹⁰	child
Alprazolam	11 hours¹¹	adult	5-6 days¹²		4741
	16 hours¹¹	elderly
		prolonged in obesity and hepatic disease; longer by 25% in Asian vs White persons
Amikacin	2-3 hours¹⁰		10-15 hours¹⁰		236
					8584
					250
Amiodarone	26-107 days¹³		not applicable		36721
	61 days¹³	N-desethylamiod-arone
Amitriptyline	10-28 hours¹⁰	amitriptyline	2-6 days¹⁰	amitriptyline	423
	18-93 hours¹⁰	nortriptyline, adult	4-21 days¹⁰	nortriptyline, adult	94031 (panel)^c,d
	14-22 hours¹⁰	nortriptyline, child	3-5 days¹⁰	nortriptyline, child
Amoxapine	8-30 hours¹³		not given		94031 (panel)^c,d
Amoxicillin	3.7 hours¹³	full-term neonates	2 days¹⁴		94095
	1-2 hours¹³	infants, children
	0.7-1.4 hours¹³	adults
Amphetamine	9.0-12.7 hours¹³	children 6-12 years, D-amphetamine	not given		14744
	10.0-15.3 hours¹³	children 6-12 years, L-amphetamine
	10.0-12.4 hours¹³	adults, D-amphetamine
	11.7-15.3 hours¹³	adults, L-amphetamine
Aripiprazole	75 hours¹⁵		14 days¹⁵		15922
					94529 (panel)^c,e
Baclofen	1.5 hours¹³	intrathecal	not given		36662
	5.7 hours¹³	tablet
	5.5 hours¹³	granules
Bismuth	21-72 days¹³	terminal half-life	not given		5374
Buprenorphine	2.2 hours¹³	intravenous	not given		93031 (panel)^c,d
	31-35 hours¹⁶	sublingual tablet
Bupropion	21 hours¹⁷		8 days¹⁷		8592
					94031 (panel)^c,d
					94032 (panel)^c,f
Brivaracetam	8-9 hours¹⁸		not given		39887
Caffeine	4-5 hours¹⁰	adult	not applicable (high variability)		305
	65-102 hours¹⁰	neonate
Carbamazepine	10-20 hours¹⁰	adult	2-6 days¹⁰	adult	26513
	8-19 hours¹⁰	child	2-4 days¹⁰	child	6071
					7933
					18948
					18949
					36676
Carbidopa	2 hours¹³		not given		3388
Carisoprodol	2 hours¹³	carisoprodol	not applicable		312
	8 hours¹³	meprobamate
Chlordiazepoxide	6-25 hours¹³	normal liver and kidney function	not given		91123
	5-30 hours¹³	end-stage renal disease
	30-63 hours¹³	liver cirrhosis
Chlorpromazine	7-119 hours¹⁹		not applicable		882
					94529 (panel)^c,e
Citalopram	24-48 hours¹³		1-2 weeks²⁰		10184
					94031 (panel)^c,d
Clomipramine	32 hours¹³	clomipramine	3 weeks²¹		30013
	69 hours¹³	norclomipramine			94031 (panel)^c,d
	69 hours¹³	desmethylclomipramine
Clonazepam	17-60 hours¹³	adult	5-7 days¹³		340
	22-33 hours¹³	child
Clozapine	12 hours¹³		5-10 days²³		1769
	22.5 hours²²	norclozapine			94529 (panel)^c,e
Codeine	3-4 hours¹³		not given		19483 (panel)^c,g
Cycloserine	10 hours¹³	normal renal function	not given		92020
Cyclosporine	6-27 hours¹⁰	influenced by underlying disease	2-6 days¹⁰		10720
					10719
					8812
					15220
Desalkylflurazepam	48-120 hours¹³		not given		70071 (panel)^c,h
Desipramine	15-24 hours¹³		not given		412
					94031 (panel)^c,d
Desmethylsertraline	62-104 hours²⁴		7 days²⁴		8871
Diazepam	20-48 hours²⁵	adult	5-14 days²⁶		90853
	18 hours²⁵	child
	100 hours²⁵	nordiazepam
		prolonged in hepatic disease
Digitoxin	4-6 days¹⁰		4 weeks²⁷		417
Digoxin	26-48 hours¹⁰	adult	7-19 days²⁸		418
	12-48 hours¹⁰	child
		prolonged in renal disease
Disopyramide	7 hours¹⁰	adult	24-48 hours¹⁰		416
	3-4 hours¹⁰	child
		prolonged in renal disease
Doxepin	12-24 hours¹⁰	adult	2-5 days¹⁰	adult	826
	30-50 hours¹⁰	child	6-13 days¹⁰	child	94031 (panel)^c,d
Doxycycline	15-25 hours¹³		not given		94093
Duloxetine	8-17 hours²⁹		3 days²⁹		16823
					94031 (panel)^c,d
Escitalopram	27-32 hours¹³		7-10 days³⁰		15857
					94031 (panel)^c,d
Eslicarbazepine	13-20 hours¹³		4-5 days³¹		92139
Ethambutol	2.5-3.6 hours¹³		not given		92018
	7-15 hours¹³	end-stage renal disease
Ethosuximide	50-60 hours¹⁰	adult	8-12 days¹⁰	adult	214
	30 hours¹⁰	child	6-10 days¹⁰	child
Everolimus	18-35 hours¹⁰		4-7 days¹⁰		18883
Felbamate	20-23 hours¹³		5 days³²		3081
Fentanyl	2-4 hours¹³	injection	not given		40065
	20-27 hours¹³	transdermal patch
Flecainide	12-27 hours³³	prolonged in renal disease	3-5 days³³		5309
Fluconazole	20-50 hours³⁴	adult	5-10 days³⁴		94097
	15.2-25.0 hours³⁴	child
	54.2 hours³⁴	neonate
		prolonged in renal disease
Flucytosine	3-5 hours³⁵	adult	18-30 hours³⁶		35692
	8 hours³⁵	infant
		prolonged in renal disease
Fluoxetine	4-6 days¹³	chronic administration	4 weeks³⁸		8389
	1-3 days¹³	acute			94031 (panel)^c,d
	7-6 days¹³	cirrhosis
Fluphenazine	13-58 hours¹⁹	hydrochloride	2 weeks³⁹		92021
	3-4 days¹⁹	enanthate			94529 (panel)^c,e
	5-12 days¹⁹	decanoate
Fluvoxamine	15.6 hours¹³	adults	5-10 days³⁷		30529
	17.4-25.9 hours¹³	elderly
Fondaparinux	17-21 hours⁴⁰	prolonged in renal disease	3 hours⁴⁰		16103
Gabapentin	5-9 hours¹⁰	adult	1-2 days¹⁰	adult, child	3557
	4-6 hours¹⁰	child
Gentamicin	2-3 hours¹⁰	prolonged in renal disease	10-15 hours¹⁰		481
					8582
					444
					8575
Haloperidol	14-41 hours¹⁹	lactate	3-9 days^b	lactate	564
	14-28 days¹⁹	decanoate	not applicable	decanoate	94529 (panel)^c,e
Heparin Anti-Xa (Low Molecular Weight Heparin)	4.5-7.0 hours⁴¹	subcutaneous injection	2-4 days⁴¹		30292
		prolonged in renal disease
Heparin Anti-Xa (Unfractionated Heparin)	30-150 min⁴⁰	dose dependent	6 hours⁴⁰		30292
Hydrocodone	3.3-4.4 hours¹³		not given		19483 (panel)^c,g
Hydromorphone	2-3 hours¹³	immediate-release	not given		19483 (panel)^c,g
	11 hours¹³	extended-release
Hydroxychloroquine	40-50 days⁴²		not given		3333
Ibuprofen	2-4 hours¹⁰	adult	24-48 hours¹⁰		5136
	1-3 hours¹⁰	child
Imipramine	6-18 hours¹³		2-5 days¹⁰		887
					94031 (panel)^c,d
Isoniazid	1-2 hours¹⁹	adult, slow inactivator (50% of Black and White individuals)	6-8 weeks^43,44		577
	2-7 hours¹⁹	adult, rapid inactivator (majority of Asian and Inuit individuals)
Itraconazole	16-28 hours⁴⁵	after single dose	15 days⁴⁵		94092
	34-42 hours⁴⁵	with repeated dosing
		prolonged in hepatic disease
Lacosamide	13 hours¹³		not given		16262
Lamotrigine	24-34 hours¹⁰	adult	3-10 days¹⁰	adult, child	22060
	~30 hours¹⁰	child
Leflunomide	14-18 days¹³		not given		18865
Levetiracetam	6-8 hours¹⁰	adult	2 days¹⁰	adult	15142
	5-7 hours¹⁰	child	1-2 days¹⁰	child	36330
		prolonged in renal disease
Levodopa	3.5 hours¹³		not given		3388
	1.5 hours¹³	when administered with carbidopa
Lidocaine	1-2 hours¹⁰	prolonged in hepatic disease	8-10 hours¹⁰		605
Lithium	24 hours¹⁰	average in young healthy subjects	3-4 days¹⁰		613
		varies with renal function
Lorazepam	18 hours¹³	children 2-12 years	5 days¹³	capsules	70071 (panel)^c,h
	42 hours¹³	neonates
	28 hours¹³	adolescents
	18 hours¹³	end stage renal disease
	12 hours¹³	tablets, adults
	20.2 hours¹³	capsules, adults
Loxapine	4-12 hours¹³		not given		94529 (panel)^c,e
Meperidine	2-5 hours¹⁹		not given		411
Meprobamate	6-16 hours¹³		not given		312
Mesoridazine	24-48 hours⁴⁶		not given		94529 (panel)^c,e
Methotrexate	3-10 hours^10,19	psoriasis, rheumatoid arthritis, or low-dose therapy adult	24-48 hours¹⁰	adult, child	648
	8-15 hours¹⁹	high-dose therapy, adult
	5-9 hours¹⁰	child
Midazolam	2-6 hours¹³		not given		70071 (panel)^c,h
Mirtazapine	20-40 hours¹⁰		not given		30348
					94031 (panel)^c,d
Molindone	1.5 hours¹³		not given		94529 (panel)^c,e
Morphine	2-4 hours¹³	immediate release	not given		6215
	11-13 hours¹³	extended release
Mycophenolic acid	8-18 hours¹⁰	adult	not applicable		10662
	variable¹⁰	child
Nortriptyline	18-93 hours¹⁰	adult	4-21 days¹⁰	adult	272
	14-22 hours¹⁰	child	3-5 days¹⁰	child	423
					94031 (panel)^c,d
Olanzapine	21-54 hours⁴⁷	adult ≤65 years	7 days⁴⁷		70073
	32-81 hours⁴⁷	adult >65 years			94529 (panel)^c,e
Oxazepam	2.8-5.7 hours		not given		70071 (panel)^c,h
Oxcarbazepine	8-15 hours¹⁰	10-hydroxycarbazepine metabolite, adult	2 days¹⁰	adult	36637
	5-9 hours¹⁰	10-hydroxycarbazepine metabolite, child	1 day¹⁰	child
Oxycodone	3-5 hours⁴⁸		>24 hours⁴⁸		18885
Paliperidone	23 hours¹³	oral	not given		91895
	25-159 days¹³	intramuscular, dose dependent
Paroxetine	12-44 hours¹⁰		4-14 days⁴⁹		94031 (panel)^c,d
Pentobarbital	15-50 hours¹³		not applicable		700
Perampanel	105 hours⁵⁰		2-3 weeks⁵⁰		93744
Phenobarbital	81-117 hours¹⁰	adult	17-24 days¹⁰	adult	708
	40-70 hours¹⁰	child	8-15 days¹⁰	child	751
					7311
					7312
Phenytoin	12-36 hours¹⁰	adult	5-7 days¹⁰	adult	713
	7-29 hours¹⁰	child	2-5 days¹⁰	child	3189
					7311
					7312
Posaconazole	34 hours¹⁰		7 days¹⁰		94010
Pregabalin	6 hours⁵¹		1-2 days⁵¹		18866
Primidone	6-12 hours¹⁰	adult	30-40 hours¹⁰	adult	751
	4-6 hours¹⁰	child	20-30 hours¹⁰	child	7312
Procainamide	2-5 hours¹⁰		11-20 hours¹⁰		743
	6 hours¹⁹	N-acetyl procainamide	not applicable	N-acetyl procainamide
Propafenone	2-10 hours¹³	extensive metabolizer (>90% of population)	4-5 days⁵²		6278
	10-32 hours¹³	poor metabolizer (<10% of population)
Protriptyline	54-92 hours¹³		not given		94031 (panel)^c,d

Pyrazinamide	9-10 hours¹³		6-8 weeks^43,44		92184
Quinidine	5-12 hours¹⁰	adult	30-35 hours¹⁰	adult	766
	3-7 hours¹⁰	child	varies with age¹⁰	child
Quetiapine	6 hours⁵³		2 days⁵³		35299
					94529 (panel)^c,e
Rifampin	1-5 hours¹⁰	adult	6-8 weeks^43,44	adult	92017
	3 hours¹⁰	child	varies with age¹⁰	child
Risperidone	3 hours⁵⁴	fast metabolizer, risperidone	1 day⁵⁴	fast metabolizer, risperidone	2339 94529 (panel)^c,e
	21 hours⁵⁴	fast metabolizer, 9-hydroxyrisperidone	5-6 days⁵⁴	fast metabolizer, 9-hydroxyrisperidone
	20 hours⁵⁴	slow metabolizer, risperidone	5 days⁵⁴	slow metabolizer, risperidone
	30 hours⁵⁴	slow metabolizer, 9-hydroxyrisperidone	not applicable	slow metabolizer, 9-hydroxyrisperidone
		prolonged in renal disease
Rivaroxaban	5-9 hours¹³		not given		90981
	11-13 hours¹³	elderly
Rufinamide	6-10 hours⁵⁵		2 days⁵⁵		16296
Salicylate	2-3 hours¹⁰	adult, child	10-23 hours¹⁰	adult	805
		increases with higher doses	10-15 hours¹⁰	child
Sertraline	26 hours⁵⁶		1 week⁵⁶		8871
Sirolimus (rapamycin)	46-78 hours¹⁰	influenced by underlying disease	5-7 days¹⁰		3671 13232
Streptomycin	4-10 hours¹³	newborns	not given		92060
	2.0-4.7 hours¹³	adults, prolonged in renal disease
Tacrolimus (FK506)	4-35 hours¹⁰	adult	2-6 days¹⁰	adult	70007
	4-12 hours¹⁰	child	not applicable	child	13232
		influenced by underlying disease
Temazepam	9.5-12.4 hours¹³		not given		70071 (panel)^c,h
Theobromine	7 hours⁵⁷		not given		876
Theophylline	5-6 hours¹⁰	adult	15-55 hours¹⁰	adult	878
	4 hours¹⁰	child	5-40 hours¹⁰	child
		influenced by underlying disease
Thiocyanate	3 days¹³		not applicable		879
Thioridazine	24 hours¹³		not given		94529 (panel)^c,e
Thiothixene	24 hours¹³		not given		94529 (panel)^c,e
Tiagabine	7-9 hours¹³		2 days⁵⁸		30333
	4-7 hours¹³	with concomitant CYP3A4 inducers
Tobramycin	2-3 hours¹⁰		5-15 hours¹⁰		888
					8576
					890
					8577
Topiramate	20-30 hours¹⁰	adult	3-5 days¹⁰	adult	30965
	12-24 hours¹⁰	child	2-4 days¹⁰	child
		prolonged in renal disease
Trazodone	7-10 hours¹⁰		4 days⁵⁹		4732
					94031 (panel)^c,d
Triazolam	1.5-5.5 hours¹³		not given		70071 (panel)^c,h
Trifluoperazine	24 hours¹³		not given		94529 (panel)^c,e
Trimipramine	16-40 hours¹³		not given		94031 (panel)^c,d
Valproic Acid	8-15 hours¹⁰	adult	2-4 days¹⁰	adult, child	916
					3314
	8-11 hours¹⁰	child			6651
Vancomycin	5-11 hours¹⁰	adult	1-2 days¹⁰	adult, child	917
	3-10 hours¹⁰	child			8578
					8579
					5406
Venlafaxine	3-7 hours⁶⁰		3 days⁶⁰		94031 (panel)^c,d
Vilazodone	25 hours¹³		not given		94031 (panel)^c,d
Voriconazole	6-9 hours¹⁰	increases with dose	5-7 days^13,61-63		94096
Vortioxetine	66 hours⁶⁴		2 weeks⁶⁴		94031 (panel)^c,d
Warfarin	20-60 hours¹³	patient-specific	5-13 daysb		936
Ziprasidone	7 hours¹³	oral	not given		17286
	2-5 hours¹³	intramuscular			94529 (panel)^c,e
Zonisamide	50-70 hours¹⁰	adult	8-12 days¹⁰	adult	37852
	40-60 hours¹⁰	child	6-10 days¹⁰	child

a	Data listed are for adults unless otherwise specified.
b	Time to steady state was calculated by multiplying the half-life by 5.
c	Test codes for blood-based drug screening panels are provided for use when (a) assays for the individual drugs are unavailable to determine half-life and steady state or (b) a patient is taking multiple antidepressants and antipsychotics.
d	Panel includes amitriptyline, amoxapine, citalopram/escitalopram, clomipramine, desipramine, doxepin, duloxetine, fluoxetine, fluvoxamine, hydroxybupropion, imipramine, maprotiline, mirtazapine, nortriptyline, paroxetine, protriptyline, sertraline, trazodone, trimipramine, venlafaxine, vilazodone, and vortioxetine.
e	Panel includes aripiprazole, chlorpromazine, clozapine, fluphenazine, haloperidol, loxapine, mesoridazine, molindone, olanzapine, quetiapine, risperidone, thioridazine, thiothixene, trifluoperazine, and ziprasidone.
f	Panel includes amitriptyline, amoxapine, citalopram/escitalopram, clomipramine, desipramine, doxepin, desmethyldoxepin, duloxetine, fluoxetine, fluvoxamine, hydroxybupropion, imipramine, maprotiline, mirtazapine, nortriptyline, paroxetine, protriptyline, sertraline, trazodone, trimipramine, venlafaxine, vilazodone, and vortioxetine.
g	Panel includes codeine, hydrocodone, hydromorphone, morphine, and oxycodone.
h	Panel includes alprazolam, alpha-hydroxyalprazolam, alpha-hydroxytriazolam, chlordiazepoxide, clonazepam, desalkylflurazepam, diazepam, lorazepam, midazolam, norchlordiazepoxide, nordiazepam, oxazepam, temazepam, and triazolam.

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Gutierrez M, Abramowitz W. Steady-state pharmacokinetics of citalopram in young and elderly subjects. Pharmacotherapy. 2000;20(12):1441-1447. doi:10.1592/phco.20.19.1441.34851
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Lanoxin^®(digoxin) tablets. Prescribing information. Concordia Pharmaceuticals. December, 2016. Accessed April 7, 2025. https://www.accessdata.fda.gov/drugsatfda_docs/label/2016/020405s013lbl.pdf
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Galiana GL, Gauthier AC, Mattson RH. Eslicarbazepine acetate: a new improvement on a classic drug family for the treatment of partial-onset seizures. Drugs R D. 2017;17(3):329-339. doi:10.1007/s40268-017-0197-5
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Content reviewed 4/2025

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This Topic Brief provides the drug half-life and time to steady state for many therapeutic drugs. It also provides guidance on how to use this information when monitoring therapeutic drugs.

Test Guide List

Drug Half-Life, Steady State, and Recommended Sample Collection Time

Topic Brief

Therapeutic Drug Monitoring

Drug Half-Life, Steady State, and Recommended Specimen Collection Time

The number of half-lives to reach steady state depends on the

Kinetics of elimination: most drugs follow first-order kinetics with constant proportion of drug eliminated dependent on plasma concentration.
Compartment model of distribution: most drugs follow a 1-compartment distribution model and are rapidly and evenly distributed throughout the body.^1,3

Steady state concentrations of drugs may deviate from 5 half-lives if they

Follow non–first-order kinetics⁵ (eg, phenytoin, ethanol, and aspirin [salicylates at high concentration] follow zero-order [saturation] kinetics; elimination is independent of plasma concentration; thus, increases in dose may not correspond to increases in plasma concentrations⁶).
Have multicompartment distribution models; the drug initially enters plasma and then distributes at different rates between plasma and tissues (eg, aminoglycoside antibacterials: gentamicin, amikacin, and tobramycin⁷ [2-compartment] and antiarrhythmic amiodarone [multiple compartments]).³
Undergo extensive first-pass metabolism in the liver³

Table. Drug Half-life and Time to Steady State^a [A-F] [G-N] [O-Z]

Drug name	Half-life		Time to steady state		Test code
Acetaminophen	2-3 hours¹⁰	adult	10-20 hours¹⁰		201
	1-3 hours¹⁰	child
Alprazolam	11 hours¹¹	adult	5-6 days¹²		4741
	16 hours¹¹	elderly
		prolonged in obesity and hepatic disease; longer by 25% in Asian vs White persons
Amikacin	2-3 hours¹⁰		10-15 hours¹⁰		236
					8584
					250
Amiodarone	26-107 days¹³		not applicable		36721
	61 days¹³	N-desethylamiod-arone
Amitriptyline	10-28 hours¹⁰	amitriptyline	2-6 days¹⁰	amitriptyline	423
	18-93 hours¹⁰	nortriptyline, adult	4-21 days¹⁰	nortriptyline, adult	94031 (panel)^c,d
	14-22 hours¹⁰	nortriptyline, child	3-5 days¹⁰	nortriptyline, child
Amoxapine	8-30 hours¹³		not given		94031 (panel)^c,d
Amoxicillin	3.7 hours¹³	full-term neonates	2 days¹⁴		94095
	1-2 hours¹³	infants, children
	0.7-1.4 hours¹³	adults
Amphetamine	9.0-12.7 hours¹³	children 6-12 years, D-amphetamine	not given		14744
	10.0-15.3 hours¹³	children 6-12 years, L-amphetamine
	10.0-12.4 hours¹³	adults, D-amphetamine
	11.7-15.3 hours¹³	adults, L-amphetamine
Aripiprazole	75 hours¹⁵		14 days¹⁵		15922
					94529 (panel)^c,e
Baclofen	1.5 hours¹³	intrathecal	not given		36662
	5.7 hours¹³	tablet
	5.5 hours¹³	granules
Bismuth	21-72 days¹³	terminal half-life	not given		5374
Buprenorphine	2.2 hours¹³	intravenous	not given		93031 (panel)^c,d
	31-35 hours¹⁶	sublingual tablet
Bupropion	21 hours¹⁷		8 days¹⁷		8592
					94031 (panel)^c,d
					94032 (panel)^c,f
Brivaracetam	8-9 hours¹⁸		not given		39887
Caffeine	4-5 hours¹⁰	adult	not applicable (high variability)		305
	65-102 hours¹⁰	neonate
Carbamazepine	10-20 hours¹⁰	adult	2-6 days¹⁰	adult	26513
	8-19 hours¹⁰	child	2-4 days¹⁰	child	6071
					7933
					18948
					18949
					36676
Carbidopa	2 hours¹³		not given		3388
Carisoprodol	2 hours¹³	carisoprodol	not applicable		312
	8 hours¹³	meprobamate
Chlordiazepoxide	6-25 hours¹³	normal liver and kidney function	not given		91123
	5-30 hours¹³	end-stage renal disease
	30-63 hours¹³	liver cirrhosis
Chlorpromazine	7-119 hours¹⁹		not applicable		882
					94529 (panel)^c,e
Citalopram	24-48 hours¹³		1-2 weeks²⁰		10184
					94031 (panel)^c,d
Clomipramine	32 hours¹³	clomipramine	3 weeks²¹		30013
	69 hours¹³	norclomipramine			94031 (panel)^c,d
	69 hours¹³	desmethylclomipramine
Clonazepam	17-60 hours¹³	adult	5-7 days¹³		340
	22-33 hours¹³	child
Clozapine	12 hours¹³		5-10 days²³		1769
	22.5 hours²²	norclozapine			94529 (panel)^c,e
Codeine	3-4 hours¹³		not given		19483 (panel)^c,g
Cycloserine	10 hours¹³	normal renal function	not given		92020
Cyclosporine	6-27 hours¹⁰	influenced by underlying disease	2-6 days¹⁰		10720
					10719
					8812
					15220
Desalkylflurazepam	48-120 hours¹³		not given		70071 (panel)^c,h
Desipramine	15-24 hours¹³		not given		412
					94031 (panel)^c,d
Desmethylsertraline	62-104 hours²⁴		7 days²⁴		8871
Diazepam	20-48 hours²⁵	adult	5-14 days²⁶		90853
	18 hours²⁵	child
	100 hours²⁵	nordiazepam
		prolonged in hepatic disease
Digitoxin	4-6 days¹⁰		4 weeks²⁷		417
Digoxin	26-48 hours¹⁰	adult	7-19 days²⁸		418
	12-48 hours¹⁰	child
		prolonged in renal disease
Disopyramide	7 hours¹⁰	adult	24-48 hours¹⁰		416
	3-4 hours¹⁰	child
		prolonged in renal disease
Doxepin	12-24 hours¹⁰	adult	2-5 days¹⁰	adult	826
	30-50 hours¹⁰	child	6-13 days¹⁰	child	94031 (panel)^c,d
Doxycycline	15-25 hours¹³		not given		94093
Duloxetine	8-17 hours²⁹		3 days²⁹		16823
					94031 (panel)^c,d
Escitalopram	27-32 hours¹³		7-10 days³⁰		15857
					94031 (panel)^c,d
Eslicarbazepine	13-20 hours¹³		4-5 days³¹		92139
Ethambutol	2.5-3.6 hours¹³		not given		92018
	7-15 hours¹³	end-stage renal disease
Ethosuximide	50-60 hours¹⁰	adult	8-12 days¹⁰	adult	214
	30 hours¹⁰	child	6-10 days¹⁰	child
Everolimus	18-35 hours¹⁰		4-7 days¹⁰		18883
Felbamate	20-23 hours¹³		5 days³²		3081
Fentanyl	2-4 hours¹³	injection	not given		40065
	20-27 hours¹³	transdermal patch
Flecainide	12-27 hours³³	prolonged in renal disease	3-5 days³³		5309
Fluconazole	20-50 hours³⁴	adult	5-10 days³⁴		94097
	15.2-25.0 hours³⁴	child
	54.2 hours³⁴	neonate
		prolonged in renal disease
Flucytosine	3-5 hours³⁵	adult	18-30 hours³⁶		35692
	8 hours³⁵	infant
		prolonged in renal disease
Fluoxetine	4-6 days¹³	chronic administration	4 weeks³⁸		8389
	1-3 days¹³	acute			94031 (panel)^c,d
	7-6 days¹³	cirrhosis
Fluphenazine	13-58 hours¹⁹	hydrochloride	2 weeks³⁹		92021
	3-4 days¹⁹	enanthate			94529 (panel)^c,e
	5-12 days¹⁹	decanoate
Fluvoxamine	15.6 hours¹³	adults	5-10 days³⁷		30529
	17.4-25.9 hours¹³	elderly
Fondaparinux	17-21 hours⁴⁰	prolonged in renal disease	3 hours⁴⁰		16103
Gabapentin	5-9 hours¹⁰	adult	1-2 days¹⁰	adult, child	3557
	4-6 hours¹⁰	child
Gentamicin	2-3 hours¹⁰	prolonged in renal disease	10-15 hours¹⁰		481
					8582
					444
					8575
Haloperidol	14-41 hours¹⁹	lactate	3-9 days^b	lactate	564
	14-28 days¹⁹	decanoate	not applicable	decanoate	94529 (panel)^c,e
Heparin Anti-Xa (Low Molecular Weight Heparin)	4.5-7.0 hours⁴¹	subcutaneous injection	2-4 days⁴¹		30292
		prolonged in renal disease
Heparin Anti-Xa (Unfractionated Heparin)	30-150 min⁴⁰	dose dependent	6 hours⁴⁰		30292
Hydrocodone	3.3-4.4 hours¹³		not given		19483 (panel)^c,g
Hydromorphone	2-3 hours¹³	immediate-release	not given		19483 (panel)^c,g
	11 hours¹³	extended-release
Hydroxychloroquine	40-50 days⁴²		not given		3333
Ibuprofen	2-4 hours¹⁰	adult	24-48 hours¹⁰		5136
	1-3 hours¹⁰	child
Imipramine	6-18 hours¹³		2-5 days¹⁰		887
					94031 (panel)^c,d
Isoniazid	1-2 hours¹⁹	adult, slow inactivator (50% of Black and White individuals)	6-8 weeks^43,44		577
	2-7 hours¹⁹	adult, rapid inactivator (majority of Asian and Inuit individuals)
Itraconazole	16-28 hours⁴⁵	after single dose	15 days⁴⁵		94092
	34-42 hours⁴⁵	with repeated dosing
		prolonged in hepatic disease
Lacosamide	13 hours¹³		not given		16262
Lamotrigine	24-34 hours¹⁰	adult	3-10 days¹⁰	adult, child	22060
	~30 hours¹⁰	child
Leflunomide	14-18 days¹³		not given		18865
Levetiracetam	6-8 hours¹⁰	adult	2 days¹⁰	adult	15142
	5-7 hours¹⁰	child	1-2 days¹⁰	child	36330
		prolonged in renal disease
Levodopa	3.5 hours¹³		not given		3388
	1.5 hours¹³	when administered with carbidopa
Lidocaine	1-2 hours¹⁰	prolonged in hepatic disease	8-10 hours¹⁰		605
Lithium	24 hours¹⁰	average in young healthy subjects	3-4 days¹⁰		613
		varies with renal function
Lorazepam	18 hours¹³	children 2-12 years	5 days¹³	capsules	70071 (panel)^c,h
	42 hours¹³	neonates
	28 hours¹³	adolescents
	18 hours¹³	end stage renal disease
	12 hours¹³	tablets, adults
	20.2 hours¹³	capsules, adults
Loxapine	4-12 hours¹³		not given		94529 (panel)^c,e
Meperidine	2-5 hours¹⁹		not given		411
Meprobamate	6-16 hours¹³		not given		312
Mesoridazine	24-48 hours⁴⁶		not given		94529 (panel)^c,e
Methotrexate	3-10 hours^10,19	psoriasis, rheumatoid arthritis, or low-dose therapy adult	24-48 hours¹⁰	adult, child	648
	8-15 hours¹⁹	high-dose therapy, adult
	5-9 hours¹⁰	child
Midazolam	2-6 hours¹³		not given		70071 (panel)^c,h
Mirtazapine	20-40 hours¹⁰		not given		30348
					94031 (panel)^c,d
Molindone	1.5 hours¹³		not given		94529 (panel)^c,e
Morphine	2-4 hours¹³	immediate release	not given		6215
	11-13 hours¹³	extended release
Mycophenolic acid	8-18 hours¹⁰	adult	not applicable		10662
	variable¹⁰	child
Nortriptyline	18-93 hours¹⁰	adult	4-21 days¹⁰	adult	272
	14-22 hours¹⁰	child	3-5 days¹⁰	child	423
					94031 (panel)^c,d
Olanzapine	21-54 hours⁴⁷	adult ≤65 years	7 days⁴⁷		70073
	32-81 hours⁴⁷	adult >65 years			94529 (panel)^c,e
Oxazepam	2.8-5.7 hours		not given		70071 (panel)^c,h
Oxcarbazepine	8-15 hours¹⁰	10-hydroxycarbazepine metabolite, adult	2 days¹⁰	adult	36637
	5-9 hours¹⁰	10-hydroxycarbazepine metabolite, child	1 day¹⁰	child
Oxycodone	3-5 hours⁴⁸		>24 hours⁴⁸		18885
Paliperidone	23 hours¹³	oral	not given		91895
	25-159 days¹³	intramuscular, dose dependent
Paroxetine	12-44 hours¹⁰		4-14 days⁴⁹		94031 (panel)^c,d
Pentobarbital	15-50 hours¹³		not applicable		700
Perampanel	105 hours⁵⁰		2-3 weeks⁵⁰		93744
Phenobarbital	81-117 hours¹⁰	adult	17-24 days¹⁰	adult	708
	40-70 hours¹⁰	child	8-15 days¹⁰	child	751
					7311
					7312
Phenytoin	12-36 hours¹⁰	adult	5-7 days¹⁰	adult	713
	7-29 hours¹⁰	child	2-5 days¹⁰	child	3189
					7311
					7312
Posaconazole	34 hours¹⁰		7 days¹⁰		94010
Pregabalin	6 hours⁵¹		1-2 days⁵¹		18866
Primidone	6-12 hours¹⁰	adult	30-40 hours¹⁰	adult	751
	4-6 hours¹⁰	child	20-30 hours¹⁰	child	7312
Procainamide	2-5 hours¹⁰		11-20 hours¹⁰		743
	6 hours¹⁹	N-acetyl procainamide	not applicable	N-acetyl procainamide
Propafenone	2-10 hours¹³	extensive metabolizer (>90% of population)	4-5 days⁵²		6278
	10-32 hours¹³	poor metabolizer (<10% of population)
Protriptyline	54-92 hours¹³		not given		94031 (panel)^c,d

Pyrazinamide	9-10 hours¹³		6-8 weeks^43,44		92184
Quinidine	5-12 hours¹⁰	adult	30-35 hours¹⁰	adult	766
	3-7 hours¹⁰	child	varies with age¹⁰	child
Quetiapine	6 hours⁵³		2 days⁵³		35299
					94529 (panel)^c,e
Rifampin	1-5 hours¹⁰	adult	6-8 weeks^43,44	adult	92017
	3 hours¹⁰	child	varies with age¹⁰	child
Risperidone	3 hours⁵⁴	fast metabolizer, risperidone	1 day⁵⁴	fast metabolizer, risperidone	2339 94529 (panel)^c,e
	21 hours⁵⁴	fast metabolizer, 9-hydroxyrisperidone	5-6 days⁵⁴	fast metabolizer, 9-hydroxyrisperidone
	20 hours⁵⁴	slow metabolizer, risperidone	5 days⁵⁴	slow metabolizer, risperidone
	30 hours⁵⁴	slow metabolizer, 9-hydroxyrisperidone	not applicable	slow metabolizer, 9-hydroxyrisperidone
		prolonged in renal disease
Rivaroxaban	5-9 hours¹³		not given		90981
	11-13 hours¹³	elderly
Rufinamide	6-10 hours⁵⁵		2 days⁵⁵		16296
Salicylate	2-3 hours¹⁰	adult, child	10-23 hours¹⁰	adult	805
		increases with higher doses	10-15 hours¹⁰	child
Sertraline	26 hours⁵⁶		1 week⁵⁶		8871
Sirolimus (rapamycin)	46-78 hours¹⁰	influenced by underlying disease	5-7 days¹⁰		3671 13232
Streptomycin	4-10 hours¹³	newborns	not given		92060
	2.0-4.7 hours¹³	adults, prolonged in renal disease
Tacrolimus (FK506)	4-35 hours¹⁰	adult	2-6 days¹⁰	adult	70007
	4-12 hours¹⁰	child	not applicable	child	13232
		influenced by underlying disease
Temazepam	9.5-12.4 hours¹³		not given		70071 (panel)^c,h
Theobromine	7 hours⁵⁷		not given		876
Theophylline	5-6 hours¹⁰	adult	15-55 hours¹⁰	adult	878
	4 hours¹⁰	child	5-40 hours¹⁰	child
		influenced by underlying disease
Thiocyanate	3 days¹³		not applicable		879
Thioridazine	24 hours¹³		not given		94529 (panel)^c,e
Thiothixene	24 hours¹³		not given		94529 (panel)^c,e
Tiagabine	7-9 hours¹³		2 days⁵⁸		30333
	4-7 hours¹³	with concomitant CYP3A4 inducers
Tobramycin	2-3 hours¹⁰		5-15 hours¹⁰		888
					8576
					890
					8577
Topiramate	20-30 hours¹⁰	adult	3-5 days¹⁰	adult	30965
	12-24 hours¹⁰	child	2-4 days¹⁰	child
		prolonged in renal disease
Trazodone	7-10 hours¹⁰		4 days⁵⁹		4732
					94031 (panel)^c,d
Triazolam	1.5-5.5 hours¹³		not given		70071 (panel)^c,h
Trifluoperazine	24 hours¹³		not given		94529 (panel)^c,e
Trimipramine	16-40 hours¹³		not given		94031 (panel)^c,d
Valproic Acid	8-15 hours¹⁰	adult	2-4 days¹⁰	adult, child	916
					3314
	8-11 hours¹⁰	child			6651
Vancomycin	5-11 hours¹⁰	adult	1-2 days¹⁰	adult, child	917
	3-10 hours¹⁰	child			8578
					8579
					5406
Venlafaxine	3-7 hours⁶⁰		3 days⁶⁰		94031 (panel)^c,d
Vilazodone	25 hours¹³		not given		94031 (panel)^c,d
Voriconazole	6-9 hours¹⁰	increases with dose	5-7 days^13,61-63		94096
Vortioxetine	66 hours⁶⁴		2 weeks⁶⁴		94031 (panel)^c,d
Warfarin	20-60 hours¹³	patient-specific	5-13 daysb		936
Ziprasidone	7 hours¹³	oral	not given		17286
	2-5 hours¹³	intramuscular			94529 (panel)^c,e
Zonisamide	50-70 hours¹⁰	adult	8-12 days¹⁰	adult	37852
	40-60 hours¹⁰	child	6-10 days¹⁰	child

a	Data listed are for adults unless otherwise specified.
b	Time to steady state was calculated by multiplying the half-life by 5.
c	Test codes for blood-based drug screening panels are provided for use when (a) assays for the individual drugs are unavailable to determine half-life and steady state or (b) a patient is taking multiple antidepressants and antipsychotics.
d	Panel includes amitriptyline, amoxapine, citalopram/escitalopram, clomipramine, desipramine, doxepin, duloxetine, fluoxetine, fluvoxamine, hydroxybupropion, imipramine, maprotiline, mirtazapine, nortriptyline, paroxetine, protriptyline, sertraline, trazodone, trimipramine, venlafaxine, vilazodone, and vortioxetine.
e	Panel includes aripiprazole, chlorpromazine, clozapine, fluphenazine, haloperidol, loxapine, mesoridazine, molindone, olanzapine, quetiapine, risperidone, thioridazine, thiothixene, trifluoperazine, and ziprasidone.
f	Panel includes amitriptyline, amoxapine, citalopram/escitalopram, clomipramine, desipramine, doxepin, desmethyldoxepin, duloxetine, fluoxetine, fluvoxamine, hydroxybupropion, imipramine, maprotiline, mirtazapine, nortriptyline, paroxetine, protriptyline, sertraline, trazodone, trimipramine, venlafaxine, vilazodone, and vortioxetine.
g	Panel includes codeine, hydrocodone, hydromorphone, morphine, and oxycodone.
h	Panel includes alprazolam, alpha-hydroxyalprazolam, alpha-hydroxytriazolam, chlordiazepoxide, clonazepam, desalkylflurazepam, diazepam, lorazepam, midazolam, norchlordiazepoxide, nordiazepam, oxazepam, temazepam, and triazolam.

References

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Galiana GL, Gauthier AC, Mattson RH. Eslicarbazepine acetate: a new improvement on a classic drug family for the treatment of partial-onset seizures. Drugs R D. 2017;17(3):329-339. doi:10.1007/s40268-017-0197-5
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Flecainide acetate tablets, USP. Prescribing information. Roxane Laboratories Inc. September, 2014. Accessed April 7, 2025. https://docs.boehringer-ingelheim.com/Prescribing%20Information/PIs/Roxane/Flecainide%20Acetate/Flecainide%20Acetate%20Tablets.pdf
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Content reviewed 4/2025

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Test Code 30292

Heparin, Anti-Xa

This assay is useful in measuring heparin concentration in patients treated with low molecular weight heparins (i.e. Enoxaparin/Lovenox) or unfractionated heparin. It is not intended for measurement of Rivaroxaban (Xarelto) or Fondaparinux (Arixtra).
Refer to test code 90981 for Rivaroxaban measurement and test code 16103 for Fondaparinux measurement.

Test Code 10662

Mycophenolic Acid, LC/MS/MS

Mycophenolic acid is an immunosuppressant used in tissue transplants. It prevents graft rejection by the host's immune system. It is very important to monitor its level. Too little of this drug will cause graft rejection, while too much will lead to infection. Monitoring its level is essential to optimize therapeutic effects, avoid toxicity, and assure compliance.

Test Code 15220

Cyclosporine A Trough, LC/MS/MS, Blood

Cyclosporine is a commonly used immunosuppressive drug in patients receiving transplants. LC/MS/MS methods have higher specificity for the parent compound than immunoassay. Therapeutic drug monitoring is useful to optimize dose and avoid toxicity. High cyclosporine levels can lead to nephrotoxicity; Low levels can lead to organ rejection following transplant. Peak concentrations are reached at around 3.5 hours after oral dosage. Elimination half-life is 10-27 hours.

Test Code 15142

Levetiracetam

Levetiracetam is an anticonvulsant used as adjunct therapy to treat adult partial seizures. As multiple anticonvulsants are administered, it is important to monitor its level to (1) optimize therapy, (2) assure compliance, and (3) to avoid toxicity.

Test Code 15857

Escitalopram, Serum/Plasma

Test Code 18883

Everolimus, Blood

Test Code 18948

Carbamazepine, Free

Test Code 201

Acetaminophen

Acetaminophen is an analgesic agent that may be hepatotoxic when ingested in quantities exceeding 150 mg/kg.

Test Code 214

Ethosuximide

Ethosuximide is an anticonvulsant used to treat seizures. Ethosuximide levels are monitored to assure adequate therapeutic levels are achieved and to avoid toxicity.

Test Code 2339

Risperidone and Metabolite

Therapeutic drug monitoring for effective therapy. Risperidone is rapidly converted into its hydroxy metabolite in the liver. Peak concentration of risperidone occurs in about 1 hour following oral administration and for 9-hydroxyrisperidone the peak level is reached at 3 hours (17 hours for poor metabolizers). The elimination half-life of risperidone is 3 hours (20 hours for poor metabolizers), and is 21 hours of hydroxyrisperidone (30 hours for poor metabolizers).

Test Code 236

Amikacin

Amikacin is an aminoglycoside antibiotic used in the treatment of gram-negative bacillary infections. Amikacin is potentially nephrotoxic and ototoxic and serial monitoring of peak and trough serum levels provides information to maintain safe and therapeutic levels.

Test Code 250

Amikacin, Peak and Trough

Amikacin is an aminoglycoside antibiotic used in the treatment of gram-negative bacillary infections. Amikacin is potentially nephrotoxic and ototoxic and serial monitoring of serum levels provides information to maintain safe and therapeutic levels.

Test Code 272

Nortriptyline

Nortriptyline is a tricyclic antidepressant. Therapeutic drug levels are monitored to assist the physician assessing therapeutic response and to avoid toxicity.

Test Code 30333

Tiagabine, Serum/Plasma

Therapeutic drug monitoring.

Test Code 30013

Clomipramine

Clomipramine and its active metabolite, norclomipramine are antidepressant drugs. Therapeutic drug monitoring is useful to optimize dose and to avoid toxicity.

Test Code 3081

Felbamate

Felbamate is an antiepileptic drug used to treat patients with a variety of types of seizures. Therapeutic drug monitoring is useful to optimize dose and avoid toxicity.

Test Code 30529

Fluvoxamine, Serum/Plasma

Therapeutic drug monitoring.

Test Code 312

Carisoprodol and Metabolite, Serum, Plasma or Blood

Test is for Therapeutic Drug Monitoring (scope: Carisoprodol and Meprobamate Metabolite).

Test Code 10184

Citalopram, Serum/Plasma

Test Code 10719

Cyclosporine A Peak (2 Hour), Blood

Cyclosporine (Cyclosporin A) is an immunosuppressant therapeutic agent used in the prevention of organ graft rejection. Clinical measurement of blood levels is required due to the inter-individual variability of metabolism as well as the toxicity associated with excessive dosage.

Test Code 10720

Cyclosporine A Panel (Trough, 1 Hour, 2 Hour Post)

Test Code 13232

Tacrolimus and Sirolimus, LC/MS/MS

Tacrolimus (FK506) and Sirolimus (Rapamycin) are immunosuppressive drugs used in organ transplantation to prevent graft rejection. Therapeutic drug monitoring is useful to optimize dose and avoid toxicity.

Test Code 3314

Valproic Acid, Free

Valproic acid is used as an anticonvulsant to treat certain types of seizures, to prevent migraine headahces, and to treat various psychiatric illnesses such as bipolar disorder and aggression. Drugs that compete from protein-binding sites with valproic acid, can increase the concentration of valproic acid. Measurement of the free concentration is useful if toxicity is suspected.

Test Code 37852

Zonisamide

Zonisamide is commonly used as an adjunct together with other conventional anticonvulsants. As multiple drugs are administered, it is important to monitor its level to optimize therapeutic effects, to assure compliance, and to avoid toxicity.

Test Code 40065

Fentanyl and Norfentanyl

Fentanyls are extensively used for anesthesia and analgesia. There are fentanyl transdermal patches available that are used in chronic pain management.

Test Code 416

Disopyramide

Disopyramide is useful in treating patients with cardiac arrhythmias and tachcardia. Therapeutic drug monitoring is useful to optimize dose and avoid toxicity.

Test Code 418

Digoxin

Digoxin is a cardiac glycoside derived from the digitalis plant. It is used to treat congestive heart failure and atrial dysrhythmias. Digoxin levels are monitored to assure adequate therapeutic levels are achieved and to avoid toxicity.

Test Code 423

Amitriptyline

The tricyclics are used to treat depression. Nortriptyline is an active metabolite of Amitriptyline. Therapeutic drug levels are monitored to assist the physician assessing therapeutic response and to avoid toxicity.

Test Code 444

Gentamicin, Peak and Trough

Gentamicin is an aminoglycoside antibiotic used in the treatment of gram positive and gram-negative bacterial infections, especially Pseudomonas, Proteus, Klebsiella and Staphylococcus. Gentamicin is potentially nephrotoxic and ototoxic and serial monitoring of peak and trough serum levels may provide the clinician with information to maintain safe and therapeutic levels.

Test Code 564

Haloperidol

Monitoring the haloperidol concentration is used to assure compliance and avoid toxicity of this antipsychotic drug.

Test Code 708

Phenobarbital

Phenobarbital is an anticonvulsant used for the long-term treatment of generalized tonic-clonic (grand mal) seizures and cortical focal seizures. Phenobarbital levels are monitored to assure adequate therapeutic levels are achieved and to avoid toxicity.

Test Code 878

Theophylline

Theophylline is used in the treatment of bronchial asthma as well as in the treatment of chronic obstructive pulmonary disease and episodes of prolonged apnea in pre-term infants. Theophylline levels are monitored to assure adequate therapeutic levels are achieved and to avoid toxicity.

Test Code 879

Thiocyanate

Thiocyanate is used as a biomarker for exposure to cyanides or cyanide-containing chemicals. This test is a serum-based assay that is primarily used to monitor cyanide levels in individuals receiving sodium nitroprusside infusion therapy for treatment of extreme hypertension. It can also be used to determine cyanide levels in individuals who have been exposed to certain industrial chemicals, cigarettes, or thiocyanate-containing foods [1].

Thiocyanate is a principal metabolite of

Test Code 887

Imipramine

Imipramine is a tricyclic antidepressant drug used to treat depression. Therapeutic drug monitoring is used to optimize dose and to avoid toxicity.

Test Code 882

Chlorpromazine

Chlorpromazine is a phenothiazine for treating psychosis and Tourett's syndrome. Monitoring it's level is important to optimize therapy, to avoid toxicity, and to assure compliance.

Test Code 90853

Diazepam and Metabolite

Therapeutic drug monitoring of anxiolytic drug. Nordiazepam is the active metabolite of the parent drug. Elimination half-life is 20-90 hours.

Test Code 92017

Rifampin Level

Test Code 92021

Fluphenazine, Serum/Plasma

Therapeutic drug monitoring.

Test Code 94092

Itraconazole

The antifungal drug itraconazole is active in the treatment of aspergillosis, blastomycosis, histoplasmosis, sporotrichosis, and onychomycosis. It is a protein-bound drug and thus has negligible CSF penetration. It may also be utilized in the treatment of systemic candidiasis and cryptococcosis, especially when other drugs are contraindicated or ineffective. The chronic nature of fungal infections demands constant monitoring of itraconazole levels within a pat

Test Code 94093

Doxycycline

The concentration of antimicrobial agents in body fluids, most notably serum or plasma, are used to regulate therapy to ensure effective dosing (especially with oral agents where GI absorption is in question), to monitor accumulation to help minimize toxicity, and to help evaluate the pharmacokinetics of new agents. Both peak and trough levels obtained immediately after dosing or immediately prior to new dosing, respectively, may be monitored.

Test Code 94097

Fluconazole

Fluconazole is commonly used in the treatment of various types of fungal infections. Due to the fact it is readily soluble in water it can be administered in relatively large amounts to patients. Measurement of serum drug levels may be helpful to optimize drug dosing regimens, particularly where there is non-compliance, concern about drug interactions, pharmacokinetic variability, or suspected toxicity.

Test Code 94010

Posaconazole

The antifungal drug posaconazole is indicated for prophylaxis of invasive aspergillus and candida infections in severely immunocompromised patients. It may also be used in the treatment of oropharyngeal candidiasis refractory to itraconazole and fluconazole. The chronic nature of fungal infections demands constant monitoring of posaconazole levels within a patient to ensure that adequate therapeutic levels of the drug are administered, absorbed and subsequently excreted.

Test Code 36712

Sirolimus, LC/MS/MS

Sirolimus is an immunosuppressant drug used to prevent organ graft rejection. Therapeutic drug monitoring is used to optimize dose and avoid toxicity. Peak concentrations are reached in 2 hours following oral administration. Elimination half-life in males is approximately 72 hours; in females approximately 61 hours.

Test Code 36721

Amiodarone

Amiodarone is an antiarrythmic drug. Therapeutic drug monitoring is useful to monitor compliance and avoid toxicity.

Test Code 648

Methotrexate

Methotrexate is an antimetabolite used in the treatment of certain neoplastic diseases, psoriasis and rheumatoid arthritis. In combination with other chemotherapeutic agents, high dose methotrexate doses followed by leucovorin rescue may be effective in prolonging relapse-free survival in patients with non-metastatic osteosarcoma. Methotrexate levels are monitored to assess toxicity.

Test Code 6278

Propafenone

Propafenone is a cardiac drug for treating ventricular arrhythmias. Therapeutic drug monitoring is important to optimize dose, to assure compliance, and to avoid toxicity.

Test Code 6651

Valproic Acid, Total and Free

Valproic acid is used as an anticonvulsant to treat certain types of seizures, to prevent migraine headaches, and to treat various psychiatric illnesses such as bipolar disorder and aggression. Drugs that compete for protein-binding sites with Valproic Acid, can increase the concentration of Valproic Acid. Therapeutic drug monitoring is useful to optimize dose. Measurement of the free concentration is useful if toxicity is suspected.

Test Code 8576

Tobramycin, Peak

Tobramycin is an aminoglycoside antibiotic used in the treatment of gram-negative bacterial infections, especially Pseudomonas, Proteus, Klebsiella and also Staphylococcus. Tobramycin is potentially nephrotoxic and ototoxic and serial monitoring of peak and trough serum levels may provide the clinician with information to maintain safe and therapeutic levels.

Test Code 8577

Tobramycin, Trough

Test Code 8578

Vancomycin, Peak

Vancomycin is an antibiotic used in the treatment of bacterial infections, especially methicillin-resistant staphylococci. Vancomycin is also used in treatment for penicillin-allergic patients who cannot receive or have failed to respond to other drugs, including the penicillins and/or cephalosporins and for other infections caused by vancomycin-susceptible organisms.

Test Code 8582

Gentamicin, Peak

Gentamicin is an aminoglycoside antibiotic used in the treatment of gram-positive and gram-negative bacterial infections, especially Pseudomonas, Proteus, Klebsiella and Staphylococcus. Gentamicin is potentially nephrotoxic and ototoxic. Serial monitoring of peak and trough serum levels may provide the clinician with information to maintain safe and therapeutic levels.

Test Code 8584

Amikacin, Peak

Amikacin is an aminoglycoside antibiotic used in the treatment of gram-negative bacillary infections. Amikacin is potentially nephrotoxic and ototoxic and serial monitoring of serum levels provides information to maintain safe and therapeutic levels.

Test Code 340

Clonazepam

Clonazepam is a benzodiazepine used as a tranquilizer. Clonazepam is used in treating patients with seizures and in reducing tardive dyskinesia. Therapeutic drug monitoring is useful to avoid toxicity.

Test Code 5136

Ibuprofen, Serum/Plasma

Test Code 5309

Flecainide

Monitoring the Flecainide concentration is used to assure compliance and avoid toxicity of this cardiac drug used to treat ventricular tachycardia and premature contractions.

Test Code 6215

Morphine, Free (Unconjugated), Serum

Therapeutic drug monitoring and confirmation of screen-positive results. Morphine is an active component of Depodur, Roxanol, etc. Serum half-life is 1.3 to 6.7 hours.

Test Code 766

Quinidine

Quinidine is used in the treatment of acute and chronic supraventricular arrhythmias and ectopic rhythm disturbances. Quinidine clearance can be altered by changes in plasma proteins and in renal and/or hepatic dysfunction. Both quinidine and the related isomer quinine possess antimalarial schizonticide activity. Quinidine levels are monitored to assure adequate therapeutic levels are achieved and to avoid toxicity.

Test Code 751

Primidone and Phenobarbital

Test Code 917

Vancomycin

Vancomycin is an antibiotic used in the treatment of serious bacterial infections, especially methicillin-resistant staphylococci. Vancomycin is also used in treatment for penicillin-allergic patients who cannot receive or have failed to respond to other drugs, including the penicillins and/or cephalosporins and for other infections caused by vancomycin-susceptible organisms.

Test Code 4741

Alprazolam (Xanax)

Test Code 481

Gentamicin

Test Code 700

Pentobarbital

Test Code 70007

Tacrolimus, Highly Sensitive, LC/MS/MS

Tacrolimus is an immunosuppressant drug which has been shown to be effective for the treatment of rejection following transplantation.

Test Code 7933

Carbamazepine and Metabolite, Free/Bound/Total

Carbamazepine and its metabolite (10,11-carbamazepine epoxide) are widely used for control of generalized tonic-clonic, partial-onset, complex and mixed seizure disorders. The metabolism of carbamazepine in epileptic patients has several different pathways that can be altered when the patient is co-medicated with other anticonvulsants and, therefore, it's therapeutic level should be monitored along with its metabolite in their free and protein bound states.

Test Code 92139

Eslicarbazepine

Monitoring eslicarbazepine is helpful to avoid toxicity and to use as a baseline for future therapy. There is no established reference range. Individual patient concentrations should be evaluated in context of patient's clinical condition and prior concentrations.

Test Code 16262

Lacosamide

Lacosamide is an antiepileptic medication. Monitoring the serum concentration is beneficial to ensure compliance with drug therapy.

Test Code 17286

Ziprasidone, Serum/Plasma

Test Code 19483

Opiate, Confirmation, Serum

Test Code 305

Caffeine

Coffee, tea and other beverages may contain caffeine. Caffeine is a methylxanthine found in over the counter products and in prescription medications. Small premature infants with mild respiratory distress shortly after birth may be treated with theophylline or caffeine. In neonates, a significant amount of theophylline is converted to caffeine. Since the demethylation pathway of theophylline is relatively undeveloped, caffeine levels may be elevated. Caffeine clearance rates typically reach adu

Test Code 36330

Levetiracetam, Immunoassay

LEV is currently used as an anti-epileptic drug for the treatment of adult partial seizures particularly as an add-on therapy for refractory patients. It also has potential for other anxiety and cognitive disturbances.

Test Code 412

Desipramine

Desipramine is a tricyclic antidepressant. Therapeutic drug levels are monitored to assist the physician assessing therapeutic response and to avoid toxicity.

Test Code 577

Isoniazid, Level

Test Code 70071

Benzodiazepines, Serum

Benzodiazepines are widely used as anxiolytics, sedative- hypnotics, muscle relaxants, and anticonvulsants. Benzodiazepines include drugs such as diazepam Valium®, chlordiazepoxide Librium®, oxazepam Serax®, lorazepam Ativan®, alprazolam Xanax®, clonazepam Clonopin® and triazolam Halcion®. Many common benzodiazepines are detected in urine by their metabolites oxazepam and nordiazepam. Psychological and physiological addictions, misuse and abuse of benzodiazepines have

Test Code 70073

Olanzapine

Therapeutic drug monitoring of antipsychotic drug.

Test Code 805

Salicylate

Salicylates are used in the treatment of fever, analgesia and in the treatment of acute rheumatic fever, rheumatoid arthritis and for inhibition of platelet aggregation in patients with CAD. When treating rheumatoid arthritis, salicylates reduce the inflammation in joint tissues. Salicylate levels are monitored to assess toxicity.

Test Code 890

Tobramycin, Peak and Trough

Tobramycin is an aminoglycoside antibiotic used in the treatment of gram-negative bacterial infections, especially Pseudomonas, Proteus, Klebsiella and also Staphylococcus. Tobramycin is potentially nephrotoxic and ototoxic and serial monitoring of peak and trough serum levels may provide the clinician with information to maintain safe and therapeutic levels.

Test Code 16296

Rufinamide

Rufinamide is an antiepileptic indicated for adjunctive treatment of seizures associated with Lennox-Gastaut syndrome in children and adults. As multiple antiepileptics may be administered, it may be important to (1) optimize therapy, (2) monitor compliance, and (3) avoid toxicity.

Test Code 18885

Oxycodone and Metabolite, Quantitative

For therapeutic drug monitoring of oxycodone (Oxycontin®, Percocet®, Percodan®). Oxycodone is a semisynthetic opioid analgesic. Steady state concentration is reached in 24-36 hours after initiation of therapy. Elimination half-life of oxycodone is 4.5 hours for controlled release and 3.2 hours for immediate release formulations. Peak plasma concentration of oxycodone is 11, 21, 39, 99, or 156 ng/mL after a single oral dose of 10, 20, 40, 80, or 160 mg respectively. Oxymorphone is a m

Test Code 18865

Leflunomide Metabolite

Leflunomide is an immunosuppressant medication used in the treatment of rheumatoid arthritis. Leflunomide is rapidly and extensively metabolized to teriflunomide, which is the active form of the medication. Steady state plasma concentrations in patients receiving recommended daily dosages: up to 63,000 ng/mL. It is recommended that all women of childbearing potential who discontinue leflunomide and women receiving treatment who wish to become pregnant undergo the cholestyramine drug elimination

Test Code 18866

Pregabalin

Pregabalin is an anti-epileptic drug. It works by slowing down impulses in the brain that cause seizures. Pregabalin also affects chemicals in the brain that send signals across the nervous system. Pregabalin is used to control seizures and to treat fibromyalgia.

Test Code 30348

Mirtazapine, Serum/Plasma

Therapeutic drug monitoring.

Test Code 3333

Hydroxychloroquine, Blood

Test Code 3557

Gabapentin

Gabapentin is an anticonvulsant drug commonly used as adjunctive therapy to treat partial seizures. Therapeutic drug monitoring is useful to optimize dose and to avoid toxicity.

Test Code 35692

Flucytosine, Serum/Plasma

Therapeutic drug monitoring.

Test Code 4732

Trazodone, Serum

For therapeutic drug monitoring of antidepressant therapy. Peak plasma levels occur approximately 1 hour after dosing when Trazodone is taken on an empty stomach or 2 hours after dosing when taken with food. Elimination of Trazodone is biphasic, consisting of an initial phase (half-life 3-6 hours) followed by a slower phase (half-life 5-9 hours).

Test Code 743

Procainamide

Procainamide is used to treat a variety of atrial and ventricular arrhythmias. Metabolism of procainamide produces an active metabolite N-Acetylprocainamide (NAPA). The concentration of both procainamide and NAPA levels are monitored to assure adequate therapeutic levels of procainamide are achieved and to avoid toxicity.

Test Code 8871

Sertraline and Desmethylsertraline, Serum/Plasma

Sertraline (Zoloft^® ) is a psychiatric drug indicated for the treatment of major depression and obsessive-compulsive disorders. Its clinical efficacy is similar to that of the traditional antidepressants but are thought to be mediated through inhibition of serotonin reuptake in the brain.

Test Code 888

Tobramycin

Test Code 8812

Cyclosporine A Trough, Blood

Cyclosporine (Cyclosporin A) is an immunosuppressant therapeutic agent used in the prevention of organ graft rejection. Measurement of blood levels is recommended due to the inter-individual variability of metabolism as well as the toxicity associated with excessive dosage.

Test Code 8592

Bupropion and Metabolite, Serum/Plasma

Bupropion is an antidepressant for treating mental depression. Monitoring its level is important to optimize therapy, to avoid toxicity and to assure compliance.

Test Code 14744

Amphetamine, Confirmation, Blood

Test Code 16103

Fondaparinux Sodium (Xa Inhibition)

Fondaparinux sodium (Arixtra) is a factor Xa inhibitor indicated for the prophylaxis and treatment of deep venous thrombosis and pulmonary embolism in certain patient populations. The antithrombotic activity of Arixtra is the result of antithrombin III-mediated selective inhibition of Factor Xa. Neutralization of factor Xa interrupts thrombin formation and thrombus development. The anti-Factor Xa activity of the drug can be measured using the chromogenic anti-Xa method using Arixtra as the calib

Test Code 15922

Aripiprazole, Quantitative, Serum/Plasma

Aripiprazole (Abilify^®) is an atypical antipsychotic and antidepressant used in the treatment of schizophrenia, bipolar disorder, and clinical depression. The analysis of aripiprazole is used to monitor compliance with drug therapy.

Test Code 16823

Duloxetine, Serum/Plasma

Antidepressant.

Test Code 1769

Clozapine

Clozapine is an atypical antipsychotic agent. Norclozapine has minimal therapeutic activity.

Test Code 18949

Carbamazepine, Total

Test Code 22060

Lamotrigine

Lamotrigine is an anticonvulsant drug used as adjunctive treatment for refactory partial seizures.

Test Code 26513

Carbamazepine and Metabolite, Total

Test Code 3189

Phenytoin, Free

Phenytoin is used singly or in combination with other anticonvulsants to treat grand mal epilepsy. Monitoring the serum levels of antiepileptic drugs has increased the efficiency and safety of drug therapy in epilepsy. It facilitates individualization of dosage regimen, reveals irregular drug intake and identifies the responsible agent in intoxicated patients on multiple drug therapy. Free phenytoin is especially useful in patients with altered phenytoin binding to protein, e.g., uremia or indiv

Test Code 30965

Topiramate

Topiramate is an anticonvulsant used as an adjunctive treatment of partial-onset epilepsy. Therapeutic drug monitoring is useful to optimize dose and avoid toxicity.

Test Code 35299

Quetiapine, Serum/Plasma

Test Code 36637

Oxcarbazepine Metabolite

Oxcarbazepine (trileptal) is an anti-convulsant used for treating generalized tonic-clonic and partial seizures. It can be administered alone or as an adjunct to other anti-convulsants. Clinically significant effects of oxcarbazepine are observed when plasma levels of its active metabolite, 10-OH-carbazepine, are between 15 and 35 ug/mL. Toxic symptoms may occur when plasma levels exceed 35 ug/mL. The therapeutic monitoring of oxcarbazepine and its active metabolite are important for achieving p

Test Code 36662

Baclofen, Serum/Plasma

Therapeutic drug monitoring.

Test Code 36676

Carbamazepine-10,11-Epoxide, Serum/Plasma

Carbamazepine and its metabolite (10,11-Carbamazepine epoxide) are widely used for control of generalized tonic-clonic, partial-onset, complex and mixed seizure disorders. The metabolism of carbamazepine in epileptic patients has several different pathways that can be altered when the patient is co-medicated with other anticonvulsants and, therefore, its therapeutic level should be monitored along with its metabolite in their free and protein bound states.

Test Code 5406

Vancomycin, Peak and Trough

Test Code 5374

Bismuth, Blood

Excessive use of bismuth containing medications may cause renal damage and other adverse effects.

Test Code 605

Lidocaine

Lidocaine direct injection or infusion is used in the emergency treatment of ventricular arrhythmias caused by acute myocardial infarction, open-heart surgery. It is also used for topical anesthesia administered as a gel or by injection. Lidocaine levels are monitored to assure adequate therapeutic levels are achieved and to avoid toxicity.

Test Code 6071

Carbamazepine and Metabolite Free

Test Code 613

Lithium

Lithium is used to treat manic-depressive disorders and the manic phase of affective disorders, including mania. The therapeutic window is relatively small. Therapeutic drug monitoring is useful to optimize dose and avoid toxicity.

Test Code 7311

Anticonvulsant Panel 1

See individual tests.

Test Code 713

Phenytoin

Phenytoin is an anticonvulsant hydantoin used for the treatment of generalized tonic-clonic (grand mal) and complex partial seizures. Phenytoin is also used for prophylaxis in neurosurgical procedures. Phenytoin levels are monitored to assure adequate therapeutic levels are achieved and to avoid toxicity.

Test Code 826

Doxepin

Doxepin is a tricyclic antidepressant. Therapeutic drug levels are monitored to assist the physician assessing therapeutic response and to avoid toxicity.

Test Code 8389

Fluoxetine

Fluoxetine is an antidepressant drug that is also used in the treatment of bulimia nervosa and obsessive-compulsive disorder. Therapeutic drug monitoring is useful to optimize dose and to avoid toxicity.

Test Code 8575

Gentamicin, Trough

Gentamicin is an aminoglycoside antibiotic used in the treatment of gram-positive and gram-negative bacterial infections, especially Pseudomonas, Proteus, Klebsiella and Staphylococcus. Gentamicin is potentially nephrotoxic and ototoxic. Serial monitoring of peak and trough serum levels may provide the clinician with information to maintain safe and therapeutic levels.

Test Code 8579

Vancomycin, Trough

Test Code 91895

Paliperidone

Paliperidone is an atypical antipsychotic drug. It is identical to 9-hydroxyrisperidone, the pharmacological active metabolite of Risperidone, and has a similar pharmacological profile as Risperidone. For treatment optimization, monitoring Paliperidone serum concentrations may be useful.

Test Code 93031

Buprenorphine and Metabolites, LC/MS/MS, Serum

The analysis of buprenorphine and metabolites is useful for the monitoring of compliance to drug therapy.

Test Code 91123

Chlordiazepoxide and Metabolites

This definitive drug assay is used to measure concentrations of chlordiazepoxide, norchlordiazepoxide, and nordiazepam in serum. This therapeutic drug monitoring assay may be used to assess if chlordiazepoxide and metabolites are within therapeutic range. Urine and oral fluid are the specimens of choice for routine monitoring of patients taking prescription drugs.

Chlordiazepoxide is a long-acting benzodiazepine used to treat adults for anxiety disorder, preoperative apprehension and an

Test Code 90981

Rivaroxaban

Rivaroxaban is an oral factor Xa inhibitor that is indicated to reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. It is also indicated for the treatment, prophylaxis, or the reduction in the risk of reoccurrence of deep vein thrombosis (DVT) or pulmonary embolism (PE). Rivaroxaban does not need to be monitored routinely, however, exceptions may include determination of failure of therapy vs. poor compliance, or potential dose adjustment required fo

Test Code 92018

Ethambutol Level

Test Code 92020

Cycloserine Level

Test Code 92060

Streptomycin, HPLC

Test Code 94031

Drug Monitoring, Antidepressants, with Confirmation, Serum

Antidepressants are medications that can be used to treat mild, moderate, and severe depression. These medications may also be used to treat anxiety and eating disorders as well as pain (fibromyalgia and neuropathic). Antidepressant drug testing is intended for use in prescription adherence monitoring of patients prescribed antidepressant medications. Adherence monitoring requires prescribed drugs to be present, and the absence of non-prescribed drugs for these patient populations. Drug testing

Test Code 94032

Drug Monitoring, Antidepressants, with Confirmation, Urine

The monitoring of the parent compounds and metabolites in urine of the group of drugs classified as Antidepressants.

Test Code 94095

Amoxicillin

The concentration of antimicrobial agents in body fluids, most notable serum or plasma, are used to regulate therapy to ensure effective dosing (especially with oral agents where GI absorption is in question), to monitor accumulation to help minimize toxicity, and to help evaluate the pharmacokinetics of new agents. Both peak and trough levels obtained immediately after dosing or immediately prior to new dosing, respectively, may be monitored.

Test Code 94096

Voriconazole

The antifungal drug voriconazole is commonly used in the treatment of various types of fungal infections. An increased fungal resistance to similar drugs of greater toxicity has promoted the use of voriconazole in treating infections caused by aspergillus and other fungal species. The chronic nature of fungal infections demands constant monitoring of voriconazole levels within a patient to ensure that adequate therapeutic levels of the drug are administered, absorbed and subsequently excreted.

Test Code 94529

Drug Monitoring, Antipsychotics, with Confirmation, Serum

Antipsychotic (AP) drugs are widely prescribed for the treatment of schizophrenia and psychosis. The so-called first generation or typical APs were developed in the 1950s and show severe side-effects such as extrapyramidal symptoms due to their pharmacological action on d2 and d4 receptors. As a measure of reducing these severe side-effects, a range of ‘second generation’ APs were developed. These newer generation drugs act considerably less on d2 and d4 receptors and therefore exhib

Test Code 916

Valproic Acid

Valproic acid is used as an anticonvulsant to treat certain types of seizures, to prevent migraine headaches and to treat various psychiatric illnesses such as bipolar disorder and aggression. Drugs that compete for protein-binding sites with valproic acid can increase the concentration of valproic acid. Therapeutic drug monitoring is useful to optimize dose. Measurement of the free concentration is useful if toxicity is suspected.

Test Code 92184

Pyrazinamide Level

Test Code 936

Warfarin, Serum/Plasma

Test Code 93744

Perampanel, Serum/Plasma

Therapeutic drug monitoring.

Test Summary

Sirolimus (Rapamycin)

This test is used to monitor immunosuppressive therapy following organ transplant.

IG/Reference Manual

Test Guide List

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Drug Half-Life, Steady State, and Recommended Sample Collection Time

Drug Half-Life, Steady State, and Recommended Sample Collection Time

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