See Alcohols (Volatiles, Solvents), Benzodiazepines. ‚
Definition
- This group of drugs includes those that reduce tension and anxiety, induce calm (sedative), or induce sleep (hypnotic). All have CNS depressant effects. Although other drugs may produce similar effects, the distinctive ability of these drugs is that they achieve their effects without altering mood or reducing sensitivity to pain.
- This class includes ethanol, chloral hydrate, glutethimide, ethchlorvynol (Placidyl), barbiturates, benzodiazepines, meprobamate (Miltown), methaqualone (Quaalude), buspirone (BuSpar), zolpidem (Ambien), and zopiclone (Imovane).
- Therapeutic range (serum):
- Chloral hydrate (metabolite trichloroethanol [TCE]): 2 " “12 µg/mL serum
- Ethchlorvynol: 2 " “8 µg/mL
- Glutethimide: 1 " “5 µg/mL
- Methaqualone: 1,000 " “4,000 ng/mL
- Meprobamate: 5 " “25 µg/mL
- Buspirone: 1 " “10 ng/mL
- Zolpidem: 25 " “300 ng/mL
- Zopiclone: 50 " “150 ng/mL
- Barbiturates:
- Ultra " “short acting (thiopental, methohexital) [approximate]: 40 µg/mL (thiopental); 3 " “10 µ/mL (methohexital for surgical anesthesia)
- Short acting (pentobarbital, secobarbital): 0.5 " “2.0 µg/mL
- Intermediate acting (amobarbital, butalbital, butabarbital): 1.0 " “5.0 µg/mL
- Long acting (phenobarbital): 5 " “15 µg/mL (sedative " “hypnotic); 15 " “40 µg/mL (anticonvulsant)
Use
- Treatment of sleeping disorders
- Reduction of anxiety
Limitations
Specific Agents
- Chloral hydrate, ethchlorvynol, glutethimide, methaqualone (currently little used in the United States; requires specific request to test)
- Chloral hydrate: measure metabolite trichloroethanol (TCE) with gas chromatography, GC/MS, LC/MS
- Ethchlorvynol: color test, gas chromatography, GC/MS; measure parent
- Glutethimide: gas chromatography, GC/MS, liquid chromatography, LC/MS; measure parent and active metabolite hydroxyglutethimide
- Methaqualone: immunoassay screening test available for this agent
- Target analyte " ”methaqualone
- Cutoff concentration (urine)] " ”300 ng/mL
- Confirmation by gas chromatography, GC/MS, liquid chromatography, LC/MS: limit of quantitation: 50 " “200 ng/mL
- Meprobamate
- Older CNS depressant
- Metabolite of muscle relaxant carisoprodol
- No immunoassay-based screening tests available
- Readily extracted in acidic neutral liquid " “liquid or solid-phase extraction scheme: GC, GC/MS, liquid chromatography, LC/MS; limit of quantitation: 500 " “1,000 ng/mL
- Buspirone
- Newer antianxiety drug
- No immunoassay-based screening tests available
- Extracted in alkaline liquid " “liquid or solid-phase extraction scheme
- GC/MS (SIM) due to low concentrations difficult to observe in full scan mode; LC/MS
- Active metabolite 1-(2-pyrimidinyl)piperazine (1-PP) may also be measured
- Limit of quantitation: 1 ng/mL
- Zolpidem
- Structurally similar to benzodiazepines
- No specific immunoassay-based screening tests available for clinical use (recently available for forensic applications)
- Readily extracted in alkaline liquid " “liquid or solid-phase extraction scheme
- Gas chromatography, liquid chromatography, GC/MS, LC/MS
- Limit of quantitation: 10 " “50 ng/mL
- Zopiclone
- Newer hypnotic
- No immunoassay-based screening tests currently available for clinical use
- Readily extracted in neutral liquid " “liquid or SPE extraction scheme
- Unstable in acidic and basic conditions
- Gas chromatography, GC/MS, liquid chromatography, LC/MS; may thermally degrade depending on gas chromatography, GC/MS operating parameters
- Limit of quantitation: 10 " “50 ng/mL