Lorazepam

Comparative studies

In a multicenter, randomized, double-blind comparison of diazepam (0.15 mg/kg followed by phenytoin 18 mg/kg), lorazepam (0.1 mg/kg), phenobarbital (15 mg/kg), and phenytoin (18 mg/kg) in 518 patients with generalized convulsive status epilepticus, lorazepam was more effective than phenytoin and at least as effective as phenobarbital or diazepam plus phenytoin [ ]. Drug-related adverse effects did not differ significantly among the treatments and included hypoventilation (up to 17%), hypotension (up to 59%), and cardiac rhythm disturbances (up to 9%).

Intramuscular lorazepam 4 mg has been compared with the combination of intramuscular haloperidol 10 mg + promethazine 50 mg in 200 emergency psychiatric patients with agitation, aggression, or violence [ ]. The treatments were comparably effective and well tolerated overall, but two patients who took lorazepam had moderate adverse effects: one had worse bronchial asthma and one had nausea and dizziness.

Placebo-controlled studies

The use of intravenous benzodiazepines administered by paramedics for the treatment of out-of-hospital status epilepticus has been evaluated in a double-blind, randomized trial in 205 adults [ ]. The patients presented either with seizures lasting 5 minutes or more or with repetitive generalized convulsive seizures and were randomized to receive intravenous diazepam 5 mg, lorazepam 2 mg, or placebo. Status epilepticus was controlled on arrival at the hospital in significantly more patients taking benzodiazepines than placebo (lorazepam 59%, diazepam 43%, placebo 21%). The rates of respiratory or circulatory complications related to drug treatment were 11% with lorazepam, 10% with diazepam, and 23% with placebo, but these differences were not significant.

Respiratory

Patients receiving intravenous benzodiazepines must be monitored for respiratory depression, which may demand artificial ventilation during intensive treatment. Lorazepam may cause less respiratory depression than diazepam at equieffective dosages [ ].