Diazapam

Химические свойства

Light Yellow Crystalline Solid

Использование

Anxiolitic; muscle relaxant (skeletal); anticonvulsant. Controlled substance (depressant)

Общее описание

Off-white to yellow crystalline powder. Practically odorless. Tasteless at first with a bitter aftertaste.

Реакции воздуха и воды

Hydrolysis occurs in aqueous solutions with a maximum stability around pH 5. . Insoluble in water.

Пожароопасность

Flash point data for Diazapam are not available; however, Diazapam is probably combustible.

Биологическая активность

Ligand at the GABA A receptor benzodiazepine modulatory site. Anxiolytic, anticonvulsant and sedative/hypnotic agent.

Фармакокине?тика

The second group of antispastic drugs to be developed were the benzodiazepines, typified by diazepam. Diazepam exerts its skeletal muscle relaxant effect by binding as an agonist at the benzodiazepine receptor of the GABAA receptor complex, which enhances GABA potency to increase chloride conductance. The muscle relaxant properties of classical benzodiazepines, such as diazepam, appear to be mediated mainly by the GABAA α2 and α3 subunits. The result is neuronal hyperpolarization, probably at both supraspinal and spinal sites for spasmolytic activity. Its actions are sufficient to relieve spasticity in patients with lesions affecting the spinal cord and in some patients with cerebral palsy.

Побочные эффекты

Few high-quality clinical trials have evaluated diazepam as a muscle relaxant, but these few suggest that diazepam is no more efficacious than, for example, carisoprodol, cyclobenzaprine, or tizanidine (i.e., efficacy is marginal). Moreover, diazepam produces drowsiness and fatigue in most patients at doses required to significantly reduce muscle tone.

Профиль безопасности

Poison by ingestion, parenteral, subcutaneous, intravenous, and intraperitoneal routes. Moderately toxic by skin contact. Questionable carcinogen with experimental tumorigenic data. Human systemic effects: dermatitis, effect on inflammation or mediation of inflammation, change in cardiac rate, somnolence, respiratory depression, and other respiratory changes, visual field changes, diplopia (double vision), change in motor activity, muscle contraction or spasticity, ataxia (loss of muscle coordination), an antipsychotic and general anesthetic. Human reproductive effects by ingestion and intravenous routes causing developmental abnormalities of the fetal cardiovascular (circulatory) system and postnatal effects. Experimental teratogenic and reproductive effects. Human mutation data reported. An allergen. A drug for the treatment of anxiety. When heated to decomposition it emits very toxic fumes of Cl and NOx.

Метаболизм

Diazepam is rapidly and completely absorbed after oral administration. Maximum peak blood concentration occurs in 2 hours, and elimination is slow, with a half-life of approximately 20 to 50 hours. As with chlordiazepoxide, the major metabolic product of diazepam is N-desmethyldiazepam, which is pharmacologically active and undergoes even slower metabolism than its parent compound. Repeated administration of diazepam or chlordiazepoxide leads to accumulation of N-desmethyldiazepam, which can be detected in the blood for more than 1 week after discontinuation of the drug. Hydroxylation of N-desmethyldiazepam at the 3-position gives the active metabolite oxazepam.

Перевозки

UN2811 Toxic solids, organic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required. UN3249 Medicine, solid, toxic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials.