Alprazolam
PsicodepresoresC58-chloro-1-methyl-6-phenyl-4H-[1,2,4]triazolo[4,3-a][1,4]benzodiazepine
Estructura molecular
Datos: PubChem CID 2118 — National Library of Medicine
Efectos
Mecanismo de acción
Se une al sitio de benzodiazepinas del receptor GABA-A, un receptor ionotrópico de cloruro. Esta unión produce un cambio conformacional que aumenta la frecuencia de apertura del canal de cloro cuando el GABA se une, potenciando la inhibición neuronal. Tiene alta afinidad por las subunidades α1, α2, α3 y α5 del receptor GABA-A.
Vida media
Vida media de eliminación plasmática media de 11.2 horas (rango 6.3-26.9 horas) en adultos sanos. En ancianos, la vida media media es de 16.3 horas (rango 9.0-26.9 horas).
Toxicidad
IDENTIFICATION AND USE: Alprazolam forms white to off-white, solid crystals. Classification: Psycholeptics, anxiolytics, and benzodiazepine derivatives. HUMAN EXPOSURE AND TOXICITY: Alprazolam, a widely used drug, has widespread, nonspecific depressant effects on the central nervous system, similar to other benzodiazepines. Alprazolam is used as an anxiolytic drug for generalized anxiety disorder and it has been reported to produce sedation and anterograde amnesia. Manifestations of alprazolam overdosage include somnolence, confusion, impaired coordination, diminished reflexes and coma. Death has been reported in association with overdoses of alprazolam by itself, as it has with other benzodiazepines. In addition, fatalities have been reported in patients who have overdosed with a combination of a single benzodiazepine, including alprazolam, and alcohol; alcohol levels seen in some of these patients have been lower than those usually associated with alcohol-induced fatality. Benzodiazepines can potentially cause fetal harm when administered to pregnant women. The newborn of a mother reporting alprazolam use during pregnancy presented with respiratory distress and clinical features consistent with neonatal withdrawal syndrome or neonatal sepsis of vertical transmission. Following ingestion of 10 mg of alprazolam, a 34 year old patient exhibited dangerous aggressive behavior. Five months later he presented with evidence of major depression. ANIMAL STUDIES: A retrospective study was conducted of 415 alprazolam ingestions in dogs: 238 suspected alprazolam toxicoses in dogs were evaluated. Clinical signs were ataxia/disorientation, depression, hyperactivity, vomiting, weakness, tremors, vocalization, tachycardia, tachypnea, hypothermia, diarrhea, and increased salivation that developed within 10-30 min post-ingestion. Other experiments in animals have indicated cardiopulmonary collapse can occur following massive intravenous doses of alprazolam. No evidence of carcinog
Farmacología
Benzodiazepina de acción corta a intermedia con potentes propiedades ansiolíticas. Indicada para trastorno de ansiedad generalizada y trastorno de pánico. Inicio de acción rápido (15-30 min). Alto potencial de dependencia física con síndrome de abstinencia que puede incluir convulsiones. Metabolismo hepático vía CYP3A4.
Efectos en el organismo
Farmacocinética
Vida media de eliminación plasmática media de 11
1-2 horas
4-6 horas
15-30 minutos (oral)
80-90% (oral)
Hígado (CYP3A4)
Renal
Se absorbe rápidamente por vía oral con Cmáx en 1-2 horas. Biodisponibilidad oral del 80-100%. Volumen de distribución de 0.9-1.2 L/kg. Unión a proteínas plasmáticas del 70-80%. Atraviesa la barrera hematoencefálica.
Cronología farmacocinética
Riesgos para la salud — Calculadora de dosis
Advertencias
- Abstinencia potencialmente letal
- No combinar con opioides
Combinaciones peligrosas
Riesgo Individual (IPRS)
Moderado
IPRS v4 · escalar normalizado [0, 1]
ModeradoModelo IPRS calculado: 20 de octubre de 2018
Fuentes de datos de dosificación
Los rangos de dosificación fueron compilados a partir de Goodman & Gilman's (14ª ed.), Rang & Dale (9ª ed.) y publicaciones indexadas en PubMed. Los valores representan promedios poblacionales para la vía de administración principal y no consideran variabilidad individual, tolerancia, peso corporal ni interacciones.