Dosing and uses of Halcion (triazolam)
Adult dosage forms and strengths
tablet: Schedule IV
- 0.125mg
- 0.25mg
Insomnia (Hypnotic)
0.125-0.25 mg PO qHs
Maximum dose: 0.5 mg PO qHs
Hepatic Impairment
Administer a lower dose; avoid use in cirrhosis
Pediatric dosage forms and strengths
Safety & efficacy not established
Geriatric dosage forms and strengths
Initiate a lower dose of 0.125 mg at bedtime; not to exceed 0.25 mg/day
Halcion (triazolam) adverse (side) effects
>10%
Drowsiness (14%)
1-10%
Headache (5-10%)
Dizziness (5-10%)
Nervousness (5-10%)
Ataxia (4-5%)
Lightheadedness (4-5%)
N/V (4-5%)
<1%
Anterogade amnesia
Paradoxical reactions
Travelers amnesia-especially if combined with EtOH
Confusion
Cramps
Fatigue
Memory impairment
Depression
Visual disturbance
Xerostomia
Anterograde amnesia
Dreaming/nightmares
Confusion
Warnings
Contraindications
Documented hypersensitivity
Acute alcohol intoxication
Myasthenia gravis (allowable in limited circumstances)
Narrow angle glaucoma (questionable)
Severe respiratory depression
Depressed neuroses, psychotic reactions
IV use in shock, coma, depressed respiration, patients who recently received other respiratory depressants
Medications that significantly impair oxidative metabolism mediated by cytochrome P450 3A (CYP 3A) including ketoconazole, itraconazole, nefazodone, and several HIV protease inhibitors
Caution
Use caution in COPD, sleep apnea, renal/hepatic disease, open-angle glaucoma (questionable), impaired gag reflex, depression, suicide ideation
Anterograde amnesia may occur
Hypersensitivity reactions reported
Sleep related activities (sleep driving, sleep-cooking, sleep-eating etc) may occur
Hyperactive aggressive behavior may occur
May impair ability to perform hazardous tasks
Failure of insomnia to remit after 7 - 10 days of treatment may indicate presence of primary psychiatric and/or medical illness that should be evaluated
Increase in daytime anxiety may occur; consider therapy discontinuation if this occurs
Use caution and consider appropriate dose reduction when used concomitantly with weak or moderate CYP450 3A inhibitors
Use caution in patients with history of drug abuse or acute alcoholism; tolerance, psychological and physical dependence may occur with prolonged use
Pregnancy and lactation
Pregnancy category: X
Lactation: Avoid if breastfeeding
Minor tranquilizers should be avoided in 1st trimester of pregnancy due to increased risk of congenital malformations
Maternal use shortly before delivery is associated with floppy infant syndrome (good and consistent evidence)
Prenatal benzodiazepine exposure slightly increased oral cleft risk (limited or inconsistent evidence)
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Halcion (triazolam)
Mechanism of action
Depresses all levels of CNS (eg, limbic and reticular formation), possibly by increasing membrane permeability to chloride ions, which in turn increases the inhibitory activity of GABA on neuronal excitability.
Pharmacokinetics
Half-Life: 1.5-5.5 hr
Peak plasma time: 0.5-2 hr
Onset of action: 15-30 min
Vd: 0.8-1.8 L/kg
Protein binding: 89%
Duration: 6-7 hr
Peak plasma concentration: 1-6 ng/mL
Metabolism: CYP3A4, glucuronic acid conjugation
Metabolites: Inactive metabolites
Excretion: Urine
