The hydrochloride salt of a short-acting benzodiazepine derivative with an imidazole structure and anxiolytic, amnestic, hypnotic, anticonvulsant and sedative properties.
Midazolam binds to the benzodiazepine receptor at the gamma-aminobutyric acid (GABA) receptor-chloride ionophore complex in the central nervous system (CNS), resulting in increases in the opening of chloride channels, membrane hyperpolarization, and the inhibitory effect of GABA. This agent may also interfere with the reuptake of GABA, thereby causing accumulation of GABA in the synaptic cleft.
Sedation for dental and minor surgical procedures. Initial: Up to 2.5 mg given 5-10 mins before procedure. Repeat after at least 2 mins if needed. Usual total: 3.5-5 mg. Max total: 7.5 mg. Induction of anesthesia: 150-200 mcg/kg in premedicated patients and at least 300 mcg/kg for those who have not received premed. Resistant cases: Up to 600 mcg/kg. Sedation in critical care Initial: 30-300 mcg/kg. Maintenance: 20-200 mcg/kg/hr.
Premed in surgical procedures 70-80 mcg/kg 20-60 mins pre-op by deep injection.
Adverse drug reactions: physical and psychological dependence with withdrawal symptoms, decreased tidal volume and respiration rate, apnoea, headache, hiccup, nausea, increased appetite, vomiting, oversedation, reduced alertness, confusion, hallucinations, fatigue, dizziness, ataxia, anterograde amnesia.