Therapeutic Drug Monitoring - TDM

Therapeutic drug monitoring (TDM) refers to the clinical practice of measuring drugs and/or metabolites in blood or serum/plasma at a specific time point to determine if a patient’s drug concentrations are within the therapeutic range, and are neither subtherapeutic nor potentially toxic. The purpose of TDM is to optimize dosing to target a therapeutic plasma drug concentration while minimizing toxicity.

Tabs Content

Clinical Overview

Quick Answers

What is the purpose of therapeutic drug monitoring?

Effective drug treatment is dependent on patient adherence/compliance to prescribed medications. Drug treatment and dosage should be personalized for each patient due to interindividual variability in response to therapy. Therapeutic drug monitoring allows for personalization of drug selection and dose, evaluation of adherence, and investigation of changes in pharmacokinetics (eg, drug-drug interactions).

When should therapeutic drug monitoring be performed?

Therapeutic drug monitoring should be performed once the patient has achieved steady-state concentration, has changed drug therapy, or has had a change in response to treatment (eg, toxicity).

Which specimens are appropriate for therapeutic drug monitoring?

Whole blood, serum, and plasma specimens can be used to assess if drug dosage achieved the targeted therapeutic range and patient adherence. Urine drug and metabolite concentrations do not correlate with signs and symptoms of drug therapy or toxicity and should not be used for therapeutic drug monitoring (TDM).

How should therapeutic drug monitoring results be interpreted?

Test results should be interpreted relative to the established therapeutic range, dose-related range, or toxic range (if applicable), timing of specimen collection (eg, predose [trough], peak, or random), specimen type, and the patient’s clinical response to treatment. Results can be affected by several variables. Incorrect timing of specimen collection relative to the therapeutic range can be misleading. Response to drug therapy is also influenced by the patient’s pharmacogenetics (eg, normal, rapid, or poor drug metabolism), physical conditions (eg, pregnancy, comorbidities), and drug-drug or food-drug interactions that could lead to an increase, decrease, or inhibited response to therapy.

Indications for Testing

Not all medications require TDM, especially when the drug has a wide therapeutic index or low risk for severe adverse effects. TDM is utilized for drugs with a

Known relationship between dose and blood/serum/plasma concentrations
Narrow therapeutic window
High patient variability in pharmacokinetics (eg, drug liberation, absorption, distribution, metabolism, and elimination)
Potential for severe adverse effects (dose related)

TDM is also used to identify drug-drug or food-drug interactions and

Monitor patient compliance
Monitor status during decontamination or detoxification
Monitor changes in drug concentrations related to aging, pregnancy, or clinical status

TDM should be performed once a drug has reached steady-state concentration.

Specimen Selection

Therapeutic and toxic ranges are typically established for serum, plasma, and whole blood specimens. Urine should not be utilized for TDM.

Serum/Plasma and Whole Blood

Clinical signs and symptoms of effective drug treatment, ineffective drug treatment, and toxicity may correlate with drug and/or metabolite concentrations in serum, plasma, and/or whole blood.

Serum, plasma, or whole blood specimens are also appropriate for

Patients on dialysis
Suspected cases of malabsorption (eg, gastric bypass)
Evaluating other aspects of an individual patient’s pharmacokinetics

Whole Blood

Whole blood specimens are used for TDM of select drugs such as immunosuppressive drugs (eg, cyclosporine A, tacrolimus, everolimus, sirolimus, and thiopurine drugs) due to drug accumulation in red blood cells (RBCs).

Oral Fluid (Saliva)

Oral fluid drug concentrations tend to correlate to serum/plasma concentrations. The window of drug detection is about 1-2 days after drug use; therefore, oral fluid can be used to detect recent drug exposure. Therapeutic ranges are not well established in oral fluid.

Urine

Urine drug and metabolite concentrations do not correlate with signs and symptoms of drug therapy or toxicity; therefore, urine should not be a specimen collected for TDM. Urine drug concentrations should also not be used to extrapolate the dose that was administered.

Timing of Specimen Collection

Therapeutic ranges are typically established at the following timed blood collections after steady-state concentrations have been reached (generally 5-7 half-lives after initiation of or change in dosing).

Trough or predose (0-60 minutes before dose administration)
Peak (generally 1-2 hours after drug administration; however, this is highly drug dependent)
Randomly

Commonly Used Testing Strategy

Quantitative testing for TDM may be performed by immunoassay, high performance liquid chromatography (HPLC), or mass spectrometry. Drug results that are reported as less than the assay cutoff should be interpreted as “not detected.”

Frequently Asked Questions

What is the definition of half-life?

The half-life of a drug refers to the time it takes for 50% of the drug to be eliminated from blood.

What is the definition of steady-state concentration?

Steady-state concentration occurs when the rate of drug administration is equal to the rate of elimination. Generally, steady-state concentration can be achieved after an individual has consistently administered the drug for the duration of 5-7 half-lives (eg, if a drug has a half-life of 24 hours and is administered once a day, then steady-state concentration can be achieved after 5-7 days of drug administration).

What is the window of detection of drugs in blood, serum, or plasma specimens?

In general, the window of detection in blood, serum, and plasma is 1-2 days after drug administration.

The window of detection for drugs is dependent on several factors, including the following

Half-life of the drug
Drug dose
Frequency of drug administration
Route of administration
Drug formulation
Chemistry of the drug (eg, solubility, stability)
Patient’s age
Patient’s body composition and sex
Patient’s pathophysiology and pharmacokinetics
Coadministration of other medications
Hydration and nutrition status
Analytical limitations of testing

Can gel separator tubes be used for toxicology testing?

Gel separator tubes are not recommended for testing in toxicology. Drugs that are lipid soluble may be absorbed into the gel and may cause a falsely low drug result.

ARUP Lab Tests

The therapeutic range is based on serum predose (trough) draw at steady-state concentration.

Optimize drug therapy and monitor patient adherence

Amiodarone and Metabolite 0090161

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 0.5-2 µg/mL

Toxic level: >3 µg/mL

Digitoxin 0090085

Method: Quantitative CEDIA Immunoassay

Therapeutic range: 10-30 ng/mL

Toxic level: >45 ng/mL

Digoxin 0090080

Method: Immunoassay

Therapeutic range: 0.8-2 ng/mL

Toxic level: >2.4 ng/mL

Flecainide 0090003

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 0.2-1 µg/mL

Toxic level: >1.5 µg/mL

Mexiletine, Serum or Plasma 2011539

Method: Quantitative Liquid Chromatography/Tandem Mass Spectrometry

Therapeutic range: 0.5-2 µg/mL

Toxic level: >2 µg/mL

Procainamide and NAPA 0090151

Method: Immunoassay

Commonly expected therapeutic range for the sum of NAPA and procainamide: 5-30 µg/mL

The concentration of NAPA is dependent on many factors, including time of last procainamide dose, mode of administration, concomitant drug therapy, sample condition, time of sample collection, and individual variations in absorption, biotransformation, distribution, and excretion

Quinidine 0090245

Method: Immunoassay

Therapeutic range: 1.5-4.5 µg/mL

Toxic level: ≥5.9 µg/mL

The therapeutic range is based on serum predose (trough) draw at steady-state concentration.

Note that therapeutic ranges depend on pathogen being treated.

Optimize drug therapy and monitor patient adherence

Amikacin, Random Level 0090015

Method: Immunoassay

Trough levels

Optimal range: 4-8 µg/mL
Toxic level: ≥8.1 µg/mL

Peak levels

Optimal range: 20-30 µg/mL
Toxic level: ≥30.1 µg/mL

Amikacin, Trough Level 0090300

Method: Immunoassay

Optimal range: 4-8 µg/mL

Toxic level: ≥8.1 µg/mL

Antibiotic Level, Aztreonam 0060845

Method: Quantitative Bioassay

Normal peak serum concentration:

90-164 µg/mL with a 1 g IV dose
204-255 µg/mL with a 2 g IV dose

Antibiotic Level, Ceftazidime 2004886

Method: Bioassay

Normal peak serum concentration:

42 µg/mL with a 500 mg IV dose
69 µg/mL with a 1 g IV dose
159-186 µg/mL with a 2 g IV dose

Antibiotic Level, Meropenem 0060844

Method: Quantitative Bioassay

Normal peak serum concentration:

26 µg/mL with a 500 mg IV dose
55-62 µg/mL with a 1 g IV dose

Antibiotic Level, Nafcillin 0060843

Method: Quantitative Bioassay

Normal peak serum concentration:

7.7 µg/mL with a 1 g PO dose
7.6 µg/mL with a 1 g IM dose
40 µg/mL with a 500 mg IV dose

Antibiotic Level, Piperacillin 0060842

Method: Quantitative Bioassay

Normal peak serum concentration:

389-484 µg/mL with a 4 g IV dose of piperacillin
209 µg/mL with a 3.375 g IV dose of piperacillin/tazobactam
224 µg/mL with a 4.5 g IV dose of piperacillin/tazobactam

Antibiotic Level, Ticarcillin 0060841

Method: Quantitative Bioassay

Normal peak serum concentration: 324 µg/mL with a 3.1 g IV dose of ticarcillin/clavulanate

Antimicrobial Level - Azithromycin by HPLC, Serum or Plasma 2009359

Method: Quantitative High Performance Liquid Chromatography-Tandem Mass Spectrometry

Peak serum concentration: 0.2-0.7 µg/mL approximately 2-3 weeks post 250-500 mg dose of oral azithromycin

Rifampin and Metabolite, Serum or Plasma 3001496

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Antimicrobial Level - Streptomycin by HPLC, Serum or Plasma 2009214

Method: Quantitative High Performance Liquid Chromatography

Target range for conventional treatment of mycobacterial infections: 35-45 µg/mL approximately 1 hr after intramuscular injection or 1 hr after the end of IV infusion

Target range for high dose, three times weekly treatment of mycobacterial infection: 65-80 µg/mL approximately 1 hr after intramuscular injection or 1 hr after the end of IV infusion

Ethambutol Quantitative, Serum or Plasma 0091319

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Usual tuberculostatic (chronic) level: 2-5 µg/mL at 4 hrs after last dose

Toxic level: >10 µg/mL

Gentamicin, Peak Level 0090305

Method: Immunoassay

Optimal range: 5-10 µg/mL

Toxic level: <12 µg/mL

Gentamicin, Trough Level 0090310

Method: Immunoassay

Optimal range: 0.5-2 µg/mL

Toxic level: >2 µg/mL

Sulfonamides, Quantitative, Serum or Plasma 3001973

Method: Quantitative Spectrophotometry

Vancomycin, Peak Level 0090325

Method: Immunoassay

Optimal range: 30-40 µg/mL

Pathogens when MIC ≤1: 15 µg/mL

Complicated infections: 15-20 µg/mL

Toxic level: ≥80.1 µg/mL

Vancomycin, Random Level 0090285

Method: Fluorescence Polarization Immunoassay

Trough level (optimal): 10-20 µg/mL

Peak level (optimal): 30-40 µg/mL

Vancomycin, Trough Level 0090330

Method: Immunoassay

Optimal level: 10-20 µg /mL

Evaluate response failure to adalimumab therapy

Determine and adjust dosage or identify the need for change to another anti-TNF-α inhibitor

Adalimumab Activity and Neutralizing Antibody 2011248

Method: Cell Culture/Quantitative Chemiluminescent Immunoassay/ Semi-Quantitative Chemiluminescent Immunoassay

Adalimumab activity and adalimumab neutralizing antibody titer not detected: higher dose of adalimumab or shortening dosing interval may be appropriate

Adalimumab activity not detected and adalimumab neutralizing antibody titer ≥1:20: change to another anti-TNF-α drug may be appropriate

Adalimumab activity ≥0.65 µg/mL and adalimumab neutralizing antibody titer not detected: change to another type of therapy (not targeting TNF-α) may be appropriate

Adalimumab activity ≥0.65 µg/mL and adalimumab neutralizing antibody titer ≥1:20: repeat testing is suggested to rule out decreasing adalimumab activity and/or increasing adalimumab neutralizing antibodies

Adalimumab Activity with Reflex to Antibody 2013605

Method: Cell Culture/Quantitative Chemiluminescent Immunoassay/ Semi-Quantitative Chemiluminescent Immunoassay

Adalimumab activity and adalimumab neutralizing antibody titer not detected: higher dose of adalimumab or shortening dosing interval may be appropriate

Adalimumab activity not detected and adalimumab neutralizing antibody titer ≥1:20: change to another anti-TNF-α drug may be appropriate

Adalimumab activity ≥0.65 µg/mL and adalimumab neutralizing antibody titer not detected: change to another type of therapy (not targeting TNF-α) may be appropriate

Evaluate response failure to infliximab or biosimilar therapy

Determine and adjust dosage or identify the need for change to another anti-TNF-α inhibitor

Infliximab or Biosimilar Activity and Neutralizing Antibody 2008320

Method: Cell Culture/Quantitative Chemiluminescent Immunoassay/ Semi-Quantitative Chemiluminescent Immunoassay

Infliximab activity and infliximab neutralizing antibody titer not detected: higher dose of infliximab or shortening dosing interval may be appropriate

Infliximab activity not detected and infliximab neutralizing antibody titer ≥1:20: change to another anti-TNF-α drug may be appropriate

Infliximab activity ≥0.65 µg/mL and infliximab neutralizing antibody titer not detected: change to another type of therapy (not targeting TNF-α) may be appropriate

Infliximab activity ≥0.65 µg/mL and infliximab neutralizing antibody titer ≥1:20: repeat testing is suggested to rule out decreasing infliximab activity and/or increasing infliximab neutralizing antibodies

Infliximab or Biosimilar Activity with Reflex to Antibody 2013612

Method: Cell Culture/Quantitative Chemiluminescent Immunoassay/ Semi-Quantitative Chemiluminescent Immunoassay

Infliximab activity and infliximab neutralizing antibody titer not detected: higher dose of infliximab or shortening dosing interval may be appropriate

Infliximab activity not detected and infliximab neutralizing antibody titer ≥1:20: change to another anti-TNF-α drug may be appropriate

Infliximab activity ≥0.65 µg/mL and infliximab neutralizing antibody titer n/a: change to another type of therapy (not targeting TNF-α) may be appropriate

Aid in management of individuals receiving natalizumab therapy

Natalizumab Antibodies 2005593

Method: Qualitative Bridging Enzyme-Linked Immunosorbent Assay

Monitor treatment efficacy of low molecular weight heparin

Heparin Anti-Xa, Low Molecular Weight Heparin 0030144

Method: Chromogenic Assay

Therapeutic range based on enoxaparin brand low molecular weight heparin

Monitor warfarin treatment

Warfarin Quantitative, Serum or Plasma 0090805

Method: Quantitative High Performance Liquid Chromatography-Tandem Mass Spectrometry

The therapeutic range is based on serum predose (trough) draw at steady-state concentration.

Optimize drug therapy and monitor patient adherence

Carbamazepine Epoxide and Total 0092211

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Carbamazepine-10,11 Epoxide

Therapeutic range: 0.4-4 µg/mL
Toxic level: >15 µg/mL

Total carbamazepine

Therapeutic range: 4-12 µg/mL
Toxic level: >15 µg/mL

Carbamazepine, Free and Total, Serum or Plasma 2011763

Method: Quantitative Enzyme Multiplied Immunoassay Technique

Total carbamazepine

Therapeutic range: 4-12 µg/mL
Toxic level: >15 µg/mL

Free carbamazepine

Therapeutic range: 1-3 µg/mL
Toxic level: >3.8 µg/mL

Percent free carbamazepine: 8-35%

Carbamazepine, Total 0090260

Method: Immunoassay

Therapeutic range: 4-12 µg/mL

Toxic level: >15 µg/mL

Clobazam Quantitative, Serum or Plasma 2008597

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Therapeutic range (clobazam): 30-300 ng/mL

Therapeutic range (norclobazam): 300-3,000 ng/mL

Ethosuximide, Serum or Plasma 2010358

Method: Quantitative Enzyme Immunoassay

Therapeutic range: 40-100 µg/mL

Toxic level: >150 µg/mL

Felbamate 0094030

Method: Quantitative High Performance Liquid Chromatography

Therapeutic range: 30-60 μg/mL

Toxic level: >120 µg/mL

Gabapentin 0090057

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 2-20 µg/mL

Toxic level: not well established

Keppra (Levetiracetam) 0098627

Method: Quantitative Enzyme Immunoassay

Therapeutic range: 12-46 µg/mL

Toxic level: not well established

Lacosamide, Serum or Plasma 2003182

Method: High Performance Liquid Chromatography/Tandem Mass Spectrometry

Therapeutic range: suggested range 5-10 µg/mL

Dose-related range: 2.5-18 µg/mL

Toxic level: not well established

Lamotrigine 0090177

Method: Quantitative Enzyme Immunoassay

Therapeutic range: 2.5-15 µg/mL

Toxic level: not well established

Oxcarbazepine or Eslicarbazepine Metabolite (MHD) 0098834

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 3-35 µg/mL

Toxic level: >40 µg/mL

Perampanel Quantitative, Serum or Plasma 2013025

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Peak plasma concentration: ~460 ng/mL with daily administration of 6 mg at approximately 1.3 hrs post dose

Peak plasma concentration: ~800 ng/mL with single 12 mg dose

Phenobarbital 0090230

Method: Immunoassay

0-2 mos:

Therapeutic range: 15-30 µg/mL
Toxic level: ≥40.1 µg/mL

3 mos and older:

Therapeutic range: 15-40 µg/mL
Toxic level: ≥50.1 µg/mL

Phenobarbital, Total/Unbound/Bound, S/P 0091551

Method: Quantitative High Performance Liquid Chromatography-Tandem Mass Spectrometry

Pregabalin, Serum or Plasma 2011609

Method: Quantitative Liquid Chromatography/Tandem Mass Spectrometry

Dose-related range: 2-10 µg/mL

Toxic level: not well established

Rufinamide, Serum or Plasma 2003176

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 3-30 µg/mL

Dose-related range: 3-30 µg/mL

Toxic level: not well established

Tiagabine Quantitative, Serum/Plasma 3001184

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Therapeutic range: 20-200 ng/mL

Toxic level: >300 ng/mL

Topiramate 0070390

Method: Quantitative Enzyme Immunoassay

Therapeutic range: 5-20 µg/mL

Toxic level: not well established

Valproic Acid 0090290

Method: Fluorescence Polarization Immunoassay

Toxic level: ≥151 µg/mL

Vigabatrin Quantitative, Serum or Plasma 2011039

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Therapeutic range: 2-10 μg/mL

Toxic level: >20 μg/mL

Zonisamide 0097908

Method: Quantitative Enzyme Multiplied Immunoassay Technique

Therapeutic range: not well established

Toxic level: >80 µg/mL

Preferred test for therapeutic drug management in patients with renal failure or conditions that may alter albumin concentrations

Phenytoin, Free and Total 0090141

Method: Quantitative Enzyme Multiplied Immunoassay Technique

Total phenytoin

Therapeutic range: 10-20 µg/mL
Toxic level: >30 µg/mL

Free phenytoin

Therapeutic: 1-2.5 µg/mL
Toxic level: >2.5 µg/mL

Percent free phenytoin: 8-14%

Valproic Acid, Free and Total 0099310

Method: Quantitative Enzyme Multiplied Immunoassay Technique

Total valproic acid:

Therapeutic range: 50-125 µg/mL
Toxic level: >150 µg/mL

Free valproic acid:

Therapeutic range: 7-23 µg/mL
Toxic level: >30 µg/mL

Percent free valproic acid: 5-18%

Therapeutic drug management for patients with renal failure or conditions that may alter albumin concentrations

Phenytoin, Free 2010481

Method: Quantitative Enzyme Multiplied Immunoassay Technique

Therapeutic range: 1-2.5 µg/mL

Toxic level: >2.5 µg/mL

Optimize drug therapy and monitor patient adherence

This test can be ordered when fosphenytoin is administered

Phenytoin 0090090

Method: Enzyme Immunoassay

0-2 mos:

Therapeutic range: 6-14 µg/mL
Toxic level: ≥14.1 µg/mL

3 mos and older:

Therapeutic range: 10-20 µg/mL
Toxic level: ≥30.1 µg/mL

Optimize drug therapy and monitor patient adherence

The active metabolite of primidone is phenobarbital

Primidone and Metabolite 0090202

Method: Immunoassay

Phenobarbital
0-2 mos:

Therapeutic range: 15-30 µg/mL
Toxic level: ≥40.1 µg/mL

3 mos and older:

Therapeutic range: 15-40 µg/mL
Toxic level: ≥50.1 µg/mL

Primidone (Mysoline)
Reference interval: 5-12 µg/mL

The therapeutic range is based on serum predose (trough) draw at steady-state concentration.

Optimize drug therapy and monitor patient adherence

Antidepressant Panel Quantitative, Urine 0096048

Method: Quantitative Gas Chromatography/ Gas Chromatography-Mass Spectrometry

Drugs tested, therapeutic ranges/toxic levels:

Amitriptyline (Elavil, Vanatrip): therapeutic range/toxic level not established
Amoxapine
Clomipramine (Anafranil): therapeutic range/toxic level not established
Desipramine (Norpramin): therapeutic range, 100-300 ng/mL; toxic level, >500 ng/mL
Desmethylclomipramine
Desmethyldoxepin
Desmethyltrimipramine
Doxepin (Sinequan, Zonalon): therapeutic range/toxic level not established
Fluoxetine
Imipramine (Tofranil): therapeutic range/toxic level not established
Maprotiline
Mirtazapine
Norfluoxetine
Nortriptyline (Aventyl, Pamelor): therapeutic range, 50-150 ng/mL; toxic level, >500 ng/mL
Protriptyline (Vivactil): therapeutic range, 70-240 ng/mL; toxic level, >400 ng/mL
Trazadone
Trimipramine

Tricyclic Antidepressants, Quantitative, Serum or Plasma 2007549

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Drugs tested, therapeutic ranges/toxic levels:

Amitriptyline (Elavil, Vanatrip): therapeutic range/toxic level not established
Nortriptyline (Aventyl, Pamelor): therapeutic range, 50-150 ng/mL; toxic level, >500 ng/mL
Total amitriptyline and nortriptyline: therapeutic range, 95-250 ng/mL; toxic level, >500 ng/mL
Imipramine (Tofranil): therapeutic range/toxic level not established
Desipramine (Norpramin): therapeutic range, 100-300 ng/mL; toxic level, >500 ng/mL
Total imipramine and desipramine: therapeutic range, 150-300 ng/mL; toxic level, >500 ng/mL
Doxepin (Sinequan, Zonalon): therapeutic range/toxic level not established
Nordoxepin: therapeutic range/toxic level not established
Total doxepin and nordoxepin: therapeutic range, 100-300 ng/mL; toxic level, >500 ng/mL
Protriptyline (Vivactil): therapeutic range, 70-240 ng/mL; toxic level, >400 ng/mL
Clomipramine (Anafranil): therapeutic range/toxic level not established
Norclomipramine: therapeutic range/toxic level not established
Total clomipramine and norclomipramine: therapeutic range, 220-500 ng/mL; toxic level, >900 ng/mL

Amitriptyline and Nortriptyline, Serum or Plasma 0090158

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range (total): 95-250 ng/mL

Toxic level: >500 ng/mL

Bupropion, Serum or Plasma (Temporary Referral as of 07/01/19) 2010357

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 50-100 ng/mL

Toxic level: >400 ng/mL

Citalopram Quantitative, Serum or Plasma 2003302

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Therapeutic range: 50-110 ng/mL

Toxic level: >220 ng/mL

Clomipramine and Metabolite, Serum or Plasma 0099336

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range (total): 220-500 ng/mL

Toxic level: >900 ng/mL

Desipramine, Serum or Plasma by Tandem Mass Spectrometry 2011487

Method: Quantitative Liquid Chromatography/Tandem Mass Spectrometry

Therapeutic range: 100-300 ng/mL

Toxic level: >500 ng/mL

Doxepin and Metabolite, Serum or Plasma 0090102

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range (total): 100-300 ng/mL

Toxic level: >500 ng/mL

Escitalopram Quantitative, Serum or Plasma 0092382

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Therapeutic range: 15-80 ng/mL

Toxic level: >160 ng/mL

Fluvoxamine Quantitative, Serum or Plasma 0091234

Method: Quantitative Gas Chromatography

Therapeutic range: 60-230 ng/mL

Toxic level: >500 ng/mL

Fluoxetine and Metabolite Quantitative, Serum or Plasma 2014180

Method: Quantitative Gas Chromatography/Mass Spectrometry (GC/MS)

Therapeutic range: 120-500 ng/mL

Toxic level: >1,000 ng/mL

Imipramine and Desipramine, Serum or Plasma 0090157

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range (total): 150-300 ng/mL

Toxic level: >500 ng/mL

Nortriptyline 0090074

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 50-150 ng/mL

Toxic level: >500 ng/mL

Protriptyline, Serum or Plasma 0090106

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 70-240 ng/mL

Toxic level: >400 ng/mL

Sertraline 0098745

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Toxic level: >300 ng/mL

Trazodone 0090316

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 0.5-2.5 µg/mL

Toxic level: >4 µg/mL

Venlafaxine and Metabolite, Serum or Plasma 2007957

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range (total): 195-400 ng/mL

Toxic level: not well established

Preferred test when determining if hypoglycemia is from exposure to metformin

Serum or plasma is the preferred specimen for correlating drug use with hypoglycemia

Metformin Quantitative, Serum or Plasma 0092390

Method: Quantitative High Performance Liquid Chromatography -Tandem Mass Spectrometry

Therapeutic range: 1-2 µg/mL

Metformin-related lactic acidosis generally associated with plasma concentrations >5 µg/mL

Preferred test for evaluating if etiology of hypoglycemia is sulfonylurea ingestion

Hypoglycemia Panel, Sulfonylureas Qualitative, Serum or Plasma 2010292

Method: Qualitative Liquid Chromatography-Tandem Mass Spectrometry

The therapeutic range is based on serum predose (trough) draw at steady-state concentration.

Optimize drug therapy and monitor patient adherence

Antifungal Level, 5-Fluorocytosine (5-FC) 0060846

Method: Quantitative Bioassay

Normal peak serum concentration for 5-fluorocytosine: 30-45 µg/mL with a 2 g PO dose or 60-80 µg/mL with a 100 mg/kg/day PO dose

Trough serum concentration: not well established

Toxicity may be seen with sustained levels greater than 100 µg/mL.

Fluconazole, Quantitative by LC-MS/MS 0097621

Method: Quantitative High Performance Liquid Chromatography -Tandem Mass Spectrometry

Therapeutic range: 5-20 µg/mL

Toxic level: not well established

Itraconazole, Quantitative by LC-MS/MS 0098519

Method: Quantitative High Performance Liquid Chromatography -Tandem Mass Spectrometry

Therapeutic ranges:

Itraconazole, localized infection: >0.5 µg/mL
Itraconazole, systemic infection: >1.0 µg/mL
Hydroxyitraconazole: no therapeutic range established

Toxic level: not well established

Posaconazole, Quantitative by LC-MS/MS 2001739

Method: Quantitative High Performance Liquid Chromatography -Tandem Mass Spectrometry

Therapeutic range: >0.7 µg/mL

Toxic level: not well established

Voriconazole, Quantitation by LC-MS/MS 2001737

Method: Quantitative High Performance Liquid Chromatography -Tandem Mass Spectrometry

Therapeutic range: 1-5.5 µg/mL

Toxic level: >6 µg/mL

Monitor treatment efficacy

Clonidine, Serum or Plasma 0091362

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Therapeutic range: 1-2 ng/mL

Toxic level: not well established

Metoprolol Quantitative, Serum or Plasma 0091453

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Peak plasma concentration: 20-340 ng/mL following oral administration of multiple doses of metoprolol tartrate (50-80 mg 3 times daily)

The therapeutic range is based on serum predose (trough) draw at steady-state concentration.

Optimize drug therapy and monitor patient adherence

Aripiprazole and Metabolite, Serum or Plasma 2007945

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range (suggested): 150-500 ng/mL

Chlorpromazine (Temporary Referral as of 07/09/19) 0090870

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range:

Child (0-11 yrs): 30-80 ng/mL
Adult (≥12 yrs): 50-300 ng/mL

Toxic level:

Child (0-11 yrs): >200 ng/mL
Adult (≥12 yrs): >750 ng/mL

Clozapine and Metabolites, Serum or Plasma, Quantitative 2013433

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: not well established

Toxic level: ≥1,500 ng/mL

Fluphenazine 0099906

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 0.5-2 ng/mL

Toxic level: not well established

Haloperidol 0099640

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 5-20 ng/mL

Toxic level: >42 ng/mL

Lurasidone Quantitative, Serum or Plasma 2013018

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Mean Cmax values in serum:

Following single dose administration of 40 mg: 54 ng/mL

Following single dose administration of 80 mg: 64 ng/mL

Following steady-state administration of 40 mg: 48 ng/mL

Following steady-state administration of 80 mg: 79 ng/mL

Olanzapine (Temporary Referral as of 09/03/19) 0098833

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 20-80 ng/mL

Toxic level: not well established

Paliperidone, Serum or Plasma 2007949

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: not well established

Proposed dose-related range: 20-60 ng/mL

Toxic range: not well established

Quetiapine, Serum or Plasma 2003118

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Predose draw (trough) preferred:

Therapeutic range: 70-170 ng/mL
Toxic level: >1,000 ng/mL

Peak draw (1.5 hr post dose; not recommended):

Therapeutic range: 100-1,000 ng/mL
Toxic level: >1,500 ng/mL

Risperidone and Metabolite, Serum or Plasma 2007951

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 20-60 ng/mL

Toxic range: not well established

Ziprasidone Quantitation, Serum or Plasma 3000721

Method: Quantitative High Performance Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 50-200 ng/mL

Toxic level: >400 ng/mL

Monitor patient adherence and exposure

Lithium, Serum or Plasma 0020038

Method: Colorimetry

Therapeutic range: 0.5-1.2 mmol/L

Toxic level: ≥1.6 mmol/L

The therapeutic range is based on serum predose (trough) draw at steady-state concentration. (Note: Also refer to ARUP Consult’s Immunosuppressive Drug Optimization and Monitoring topic.)

Optimize drug therapy and monitor patient adherence

Cyclosporine A by Tandem Mass Spectrometry 0070035

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range: 100-400 ng/mL

Kidney transplant (in combination with Everolimus)

1 mo posttransplant: 100-200 ng/mL
2-3 mos posttransplant: 75-150 ng/mL
4-5 mos posttransplant: 50-100 ng/mL
6-12 mos posttransplant: 25-50 ng/mL

Heart transplant

Up to 3 mos posttransplant: 350-525 ng/mL
4 mos and older posttransplant: 145-350 ng/mL

Liver transplant: 290-525 ng/mL

Toxic level: >700 ng/mL

Cyclosporine A, 2-Hour Post Dose (C2) by Tandem Mass Spectrometry 0058902

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Renal transplant (suggested target range): 800-1,700 ng/mL

Liver transplant (suggested target range): 600-1,000 ng/mL

Everolimus by Tandem Mass Spectrometry 0092118

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range:

Kidney transplant (in combination with cyclosporine): 3-8 ng/mL

Liver transplant (in combination with tacrolimus): 3-8 ng/mL

Toxic level: >15 ng/mL

Methotrexate, Sensitive 2005405

Method: Quantitative Immunoassay

Therapeutic range:

Low dose: 0.5-1 µmol/L

High dose/24 hrs: ≤5 µmol/L

48 hrs: ≤0.5 µmol/L

72 hrs: ≤0.1 µmol/L

Mycophenolic Acid and Metabolites 2010359

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Mycophenolic acid

Therapeutic range: 1-3.5 µg/mL
Toxic level: >25 µg/mL

Mycophenolic acid glucuronide

Therapeutic range: 35-100 µg/mL
Toxic level: not well established

Sirolimus by Tandem Mass Spectrometry 0098467

Method: Quantitative High Performance Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range:

Kidney transplant (in combination with cyclosporine): 4-12 ng/mL

Toxic level: >25 ng/mL

Tacrolimus by Tandem Mass Spectrometry 0090612

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range

Kidney transplant

0-3 mos posttransplant: 7-20 ng/mL
3 mos and older: 5-15 ng/mL

Heart transplant

0-3 mos posttransplant: 10-20 ng/mL
3 mos and older: 5-15 ng/mL

Liver transplant

1-12 mos posttransplant: 5-20 ng/mL

Toxic level: >25 ng/mL

Therapeutic monitoring and evaluating full elimination of the drug (eg, toxicity, pregnancy)

Leflunomide Metabolite, Serum or Plasma 2007460

Method: High Performance Liquid Chromatography/Mass Spectrometry

Therapeutic range: 50-100 µg/mL (>40 µg/mL associated with improved individual outcome)

Toxic level: not well established

Phenotype test used to optimize therapy for patients who are taking thiopurine drugs

Thiopurine metabolite concentrations are identified to assess therapeutic and toxic concentrations

If thiopurine therapy has not been initiated, order thiopurine methyltransferase, RBC

Thiopurine Metabolites by LC-MS/MS 2014484

Method: Quantitative Liquid Chromatography/Tandem Mass Spectrometry

6-thioguanine (6-TG): >235 pmol/8 x 10(8) RBC associated with leucopenia

6-methylmercaptopurine (6-MMP): >5,700 pmol/8 x 10(8) RBC may be associated with hepatoxicity

Therapeutic monitoring and evaluating full elimination of the drug (eg, toxicity, pregnancy)

Leflunomide Metabolite, Serum or Plasma 2007460

Method: High Performance Liquid Chromatography/Mass Spectrometry

Therapeutic range: 50-100 µg/mL (>40 µg/mL associated with improved individual outcomes)

Toxic level: not well established

Optimize drug therapy and monitor patient adherence

Theophylline 0090265

Method: Enzyme Immunoassay

Therapeutic ranges

0-5 mos: 6-12 µg/mL
6 mos and older: 10-20 µg/mL

Toxic level:

0-5 mos: >20.1 µg/mL
6 mos and older: >25.1 µg/mL

The therapeutic range is based on serum predose (trough) draw at steady-state concentration. (Note: Also refer to ARUP Consult’s Pain and Addiction Management topic.)

Aid in the assessment of acetaminophen toxicity

Acetaminophen 0090001

Method: Spectrophotometry

Critical values:

Post 4-hr ingestion: >150 µg/mL
Post 12-hr ingestion: >40 µg/mL

Optimize drug therapy and monitor patient adherence

Ibuprofen Quantitative, Serum or Plasma 2014183

Method: Quantitative High Performance Liquid Chromatography/Tandem Mass Spectrometry

Aid in assessment of the etiology of anion gap acidosis

Salicylate Assay 0090251

Method: Spectrophotometry

Analgesic: 2-10 mg/dL
Anti-inflammatory: 10-30 mg/dL
Toxic level: ≥31 mg/dL or greater

The therapeutic range is based on serum predose (trough) draw at steady-state concentration.

Optimize dose, detect variable pharmacokinetics, and monitor patient adherence

Imatinib 3000539

Method: Immunoturbidimetry

Concentrations associated with an improved response:

Chronic myelogenous leukemia: >1,000 ng/mL
Gastrointestinal stromal tumor: >1,100 ng/mL

Monitor methotrexate concentration

Methotrexate, Sensitive 2005405

Method: Quantitative Immunoassay

Low dose: 0.5-1 µmol/L

High dose:

24 hrs: ≤5 µmol/L
48 hrs: ≤0.5 µmol/L
72 hrs: ≤0.1 µmol/L

Optimize drug therapy

Mitotane, Serum or Plasma 2013014

Method: Quantitative Gas Chromatography

Phenotype test used to optimize therapy for patients who are taking thiopurine drugs

Thiopurine metabolite concentrations are identified to assess therapeutic and toxic concentrations

If thiopurine therapy has not been initiated, order thiopurine methyltransferase, RBC

Thiopurine Metabolites by LC-MS/MS 2014484

Method: Quantitative Liquid Chromatography/Tandem Mass Spectrometry

6-TG: >235 pmol/8 x 10(8) RBC associated with leucopenia

6-MMP: >5700 pmol/8 x 10(8) RBC may be associated with hepatoxicity

The therapeutic range is based on serum predose (trough) draw at steady-state concentration. (Note: Also refer to ARUP Consult’s Pain and Addiction Management topic.)

Monitor patient adherence

Buprenorphine and Metabolites, Serum or Plasma, Quantitative 2012647

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Fentanyl and Metabolite, Serum or Plasma, Quantitative 2011776

Method: Quantitative Liquid Chromatography/Tandem Mass Spectrometry

Methadone and Metabolite, Serum or Plasma, Quantitative 0090699

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Opiates, Serum or Plasma, Quantitative 0092354

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Therapeutic range 2 ng/mL for the following:

Codeine

Morphine

6-acetylmorphine

Hydrocodone

Hydromorphone

Oxycodone

Oxymorphone

Propoxyphene and Metabolite, Serum or Plasma, Quantitative 2010464

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Tapentadol, Free, Serum or Plasma 3000584

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Tramadol and Metabolite, Quantitative, Serum or Plasma 2014686

Method: Quantitative High Performance Liquid Chromatography-Tandem Mass Spectrometry

(eg, benzodiazepines, barbiturates, muscle relaxants)

The therapeutic range is based on serum predose (trough) draw at steady-state concentration

Optimize drug therapy and monitor patient adherence

Alprazolam 0090010

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Dose-related ranges:

Anxiety: 10-40 ng/mL (dose, 1-4 mg/d)
Phobia and panic: 50-100 ng/mL (dose, 6-9 mg/d)

Toxic level: >100 ng/mL

Benzodiazepines, Serum or Plasma, Quantitative 2010445

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

See individual drug analytes for therapeutic ranges and toxic thresholds

Carisoprodol and Meprobamate, Serum or Plasma, Quantitative 2011450

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Carisoprodol, Serum or Plasma

Therapeutic range: <8 µg/mL
Toxic level: ≥8 µg/mL

Meprobamate, Serum or Plasma

Therapeutic range: 5-20 µg/mL
Toxic level: >40 µg/mL

Clonazepam 0090055

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Dose-related range (adult): 20-70 ng/mL (1-8 mg/d)

Toxic level: >80 ng/mL

Clorazepate (Assayed as Nordiazepam) 0090196

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Dose-related range: 100-1,500 ng/mL (based on common dosage amounts)

Toxic level: >2,500 ng/mL

Diazepam and Nordiazepam 0090076

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Diazepam

Dose-related range: 200-1,000 ng/mL (based on normal dosage amounts)

Nordiazepam

Dose-related range: 100-1,500 ng/mL (based on normal dosage amounts)
Toxic level: >2,500 ng/mL

Librium and Nordiazepam 0090148

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Librium

Therapeutic range: 500-3,000 ng/mL (based on adult dose of 5-100 mg)
Toxic level: >5,000 ng/mL

Nordiazepam

Therapeutic range: 100-1,500 ng/mL (based on normal dosages)
Toxic level: >2,500 ng/mL

Lorazepam 0090181

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Dose-related range: 50-240 ng/mL (based on adult dose 1-10 mg/d)

Toxic level: >300 ng/mL

Pentobarbital, Serum or Plasma 2011549

Method: Quantitative Gas Chromatography/Mass Spectrometry

Therapeutic range:

Sedation: 1-5 µg/mL
Intracranial pressure therapy: 25-35 µg/mL
Coma: 10-50 µg/mL

Toxic level: >10 µg/mL

Prazepam (Assayed as Nordiazepam) 0090672

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Prazepam

Dose-related range: 20-60 mg/d

Nordiazepam

Dose-related range: 100-1,500 ng/mL
Toxic level: >2,500 ng/mL

Optimize drug therapy and monitor patient adherence

Barbiturates, Serum or Plasma, Quantitative 2012201

Method: Quantitative Gas Chromatography-Mass Spectrometry

See individual drug analytes for therapeutic ranges and toxic thresholds

Screening test for benzodiazapines

Results are unconfirmed and are to be used for medical (treatment) purposes only

Benzodiazepines Detection 0090367

Method: Immunoassay

Monitor patient adherence and exposure

Ketamine and Metabolite Quantitative, Serum or Plasma 0091507

Method: Quantitative Gas Chromatography-Mass Spectrometry

Optimize drug therapy and monitor patient adherence

Zolpidem, Serum or Plasma, Quantitative 2012652

Method: Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Medical Experts

Johnson-Davis, Kamisha, PhD, DABCC, FAACC, Medical Director, Clinical Toxicology at ARUP Laboratories; Associate Professor of Clinical Pathology, University of Utah

McMillin, Gwendolyn A., PhD, Medical Director, Toxicology; Medical Director, Pharmacogenetics; and Scientific Director, Mass Spectrometry, at ARUP Laboratories; Professor of Clinical Pathology, University of Utah

References

Additional Resources

Moller M, Gareri J, Koren G. A review of substance abuse monitoring in a social services context: a primer for child protection workers. Can J Clin Pharmacol. 2010; 17(1): e177-93. PubMed

Moyer T, McMillin G. Therapeutic drugs. In Burtis CA, Ashwood ER and Burns DE, eds. Tietz Fundamentals of Clinical Chemistry, 6th ed.. MO: Saunders/Elsevier, 2008.

Moyer T, Shaw L. Therapeutic drugs and their management.. In Burtis CA, Ashwood ER and Burns DE, eds. Clinical Chemistry & Molecular Diagnostics, 4th ed. Philadelphia, PA: WB Saunders, 2005.

Riedel M, Musil R, Seemüller F, Spellmann I, Möller H, Schennach-Wolff R. Safety evaluation of zotepine for the treatment of schizophrenia. Expert Opin Drug Saf. 2010; 9(4): 659-66. PubMed

Schultz SH, North SW, Shields CG. Schizophrenia: a review. Am Fam Physician. 2007; 75(12): 1821-9. PubMed

Shin JK, Malone DT, Crosby IT, Capuano B. Schizophrenia: a systematic review of the disease state, current therapeutics and their molecular mechanisms of action. Curr Med Chem. 2011; 18(9): 1380-404. PubMed

Resources from the ARUP Institute for Clinical and Experimental Pathology®

Wong SH, Johnson-Davis KL, Garrison K, Rankin JD, Muhammad CS. Everolimus TDM using Thermo Fisher QMS immunoassay on Indiko, Beckman DxC, AU680, and AU5800 analyzers. Clin Biochem. 2017; 50(7-8): 425-430. PubMed

Wu F, Slawson MH, Johnson-Davis KL. Metabolic Patterns of Fentanyl, Meperidine, Methylphenidate, Tapentadol and Tramadol Observed in Urine, Serum or Plasma. J Anal Toxicol. 2017; 41(4): 289-299. PubMed

Educational Videos

Content Review:

May 2019

Last Update: November 2019

Therapeutic Drug Monitoring - TDM

Quick Answers

What is the purpose of therapeutic drug monitoring?

When should therapeutic drug monitoring be performed?

Which specimens are appropriate for therapeutic drug monitoring?

How should therapeutic drug monitoring results be interpreted?

Indications for Testing

Specimen Selection

Serum/Plasma and Whole Blood

Whole Blood

Oral Fluid (Saliva)

Urine

Timing of Specimen Collection

Commonly Used Testing Strategy

Frequently Asked Questions

ARUP Lab Tests

Antiarrhythmic Tests

Antibiotic Tests

Antibody Therapeutic Tests

Anticoagulant Tests

Anticonvulsant/Antiepileptic Tests

Antidepressant Tests

Antidiabetic Tests

Antifungal Tests

Antihypertensive Tests

Antipsychotic Tests

Immunosuppressant Tests

Miscellaneous Tests

Nonopioid Pain Medication Tests

Oncology/Chemotherapy Tests

Opiate/Opioid Analgesic Tests

Sedative-Hypnotics Tests

Medical Experts

References

Additional Resources

Resources from the ARUP Institute for Clinical and Experimental Pathology®

ARUP Laboratories

ARUP Websites

ARUP Consult


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Therapeutic Drug Monitoring - TDM

Quick Answers

What is the purpose of therapeutic drug monitoring?

When should therapeutic drug monitoring be performed?

Which specimens are appropriate for therapeutic drug monitoring?

How should therapeutic drug monitoring results be interpreted?

Indications for Testing

Specimen Selection

Serum/Plasma and Whole Blood

Whole Blood

Oral Fluid (Saliva)

Urine

Timing of Specimen Collection

Commonly Used Testing Strategy

Frequently Asked Questions

ARUP Lab Tests

Antiarrhythmic Tests

Antibiotic Tests

Antibody Therapeutic Tests

Anticoagulant Tests

Anticonvulsant/Antiepileptic Tests

Antidepressant Tests

Antidiabetic Tests

Antifungal Tests

Antihypertensive Tests

Antipsychotic Tests

Immunosuppressant Tests

Miscellaneous Tests

Nonopioid Pain Medication Tests

Oncology/Chemotherapy Tests

Opiate/Opioid Analgesic Tests

Sedative-Hypnotics Tests

Medical Experts

References

Additional Resources

Resources from the ARUP Institute for Clinical and Experimental Pathology®

ARUP Laboratories

ARUP Websites

ARUP Consult