Psychological and physical dependence, withdrawal syndrome; drowsiness, sedation, vertigo, headache, visual disturbances, GI disturbances, jaundice; fatigue, muscle weakness, ataxia, dizziness, confusion and depression. Potentially Fatal: Blood dyscrasias.
Potentiates action of alcohol and CNS depressants. Reduced conc with cigarette smoking by 50%. Potentially Fatal: Cimetidine and fluoxetine reduce the clearance of alprazolam. Alprazolam enhances activity of imipramine and desipramine.
Acute narrow-angle glaucoma, preexisting CNS depression or coma, resp depression, acute pulmonary insufficiency or sleep apnoea; severe hepatic impairment; pregnancy, lactation.
Alprazolam has anxiolytic, muscle-relaxant, anticonvulsant, antidepressant and sleep-modifying effects. It binds to the Î³ aminobutyric acid (GABA)-specific sites throughout the CNS, leading to an increase in the inhibitory effect of GABA on neuronal excitability. Increased neuronal permeability to chloride ions thus results in hyperpolarisation and stabilisation. Absorption: Well absorbed from the GIT (oral); peak plasma concentrations after 1-2 hrs. Distribution: Protein-binding: 70-80% Metabolism: Hepatic; converted to Î±-hydroxyalprazolam and benzophenone. Excretion: Urine (as unchanged drug and metabolites); 11-15 hrs (elimination half-life).
Dosage reduction or gradual withdrawal. Dependence. Geriatric or debilitated patients. Muscle weakness, impaired hepatic or renal function; arteriosclerosis; obesity; depression particularly suicidal tendency; chronic pulmonary insufficiency. May impair ability to drive or operate machinery. Children <18 yr.