Lorazepam shares the actions of other benzodiazepines and is used for the management of anxiety disorders or for the short-term relief of symptoms of anxiety or anxiety associated with depressive symptoms. Anxiety or tension associated with the stress of everyday life usually does not require treatment with an anxiolytic. The efficacy of lorazepam for long-term use (i.e., longer than 4 months) as an anxiolytic has not been evaluated. The need for continued therapy with the drug should be periodically reassessed.
Preoperative Sedation, Anxiolysis, and Anterograde Amnesia
Lorazepam injection is used preoperatively in adults to produce sedation, relieve anxiety, and provide anterograde amnesia. Administration of lorazepam injection is especially useful in patients with preoperative anxiety who prefer diminished recall of events associated with the day of surgery. Lorazepam injection may be used in conjunction with atropine sulfate, opiate analgesics, other parenterally administered analgesics, commonly used anesthetics, and skeletal muscle relaxants.
Lorazepam is used IV for the management of status epilepticus and IV lorazepam or diazepam generally is considered the drug of choice for termination of this condition. The efficacy of IV lorazepam was established in 2 multicenter controlled trials in patients (mostly 18-65 years of age) with tonic-clonic status epilepticus, simple partial and complex partial status epilepticus, or absence status.
In a double-blind, randomized, active-control study in 58 patients with status epilepticus, efficacy of lorazepam (given as a 2-mg IV dose with an additional 2-mg IV dose if necessary) was compared with that of diazepam (given as a 5-mg IV dose with an additional 5-mg IV dose if necessary). In this study, 80 or 57% of patients receiving lorazepam or diazepam, respectively, were considered responders, defined as the percentage of patients in whom seizures were terminated within 10 minutes after administration of the drug and who continued to be seizure-free for at least an additional 30 minutes. When patients who did not respond to the initial doses of lorazepam or diazepam received an additional 2-4 mg of lorazepam or 5-10 mg of diazepam, respectively, the overall response rate increased to 93 or 86%, respectively. In addition, in another clinical study in adults with status epilepticus, 61, 57, and 76% of patients receiving 1, 2, and 4 mg of lorazepam, respectively, reportedly were responders (as defined above). Although IV diazepam has been used more extensively, some clinicians prefer IV lorazepam because of its more prolonged duration of effect. For continuing seizures, a long-acting anticonvulsant (e.g., IV phenytoin, IV fosphenytoin) can be added presumptively to IV benzodiazepine therapy for the management of status epilepticus.
Sedation in Critical-care Settings
Lorazepam, administered by an intermittent injection or continuous IV infusion, has been used for sedation of intubated and mechanically ventilated adults and children during treatment in a critical-care setting. Lorazepam has been shown to be as effective as midazolam or propofol in terms of the level of sedation and the time required to achieve adequate sedation, and usually, the number of daily dose adjustments. In one study, midazolam IV infusions required more frequent dosage adjustments to maintain the desired level of sedation than lorazepam. Some clinicians recommend the use of lorazepam in most patients that require prolonged sedation in a critical-care setting, while propofol or midazolam is the preferred drug for short-term sedation. Because of the lorazepam's slow onset of action, the drug is not effective for the treatment of acute agitation and midazolam or diazepam is preferred for rapid sedation of the acutely agitated patient.
Lorazepam also has been used in the management of schizophrenia and may be helpful for the management of anxiety, agitation, and sleep disturbances that are often present during the acute phase of schizophrenia in patients receiving antipsychotic therapy. In addition, the drug also has been used in patients who experience akathisia while receiving antipsychotic drugs and for the treatment of acute catatonic reactions, whether associated with schizophrenia or other conditions.
Cancer Chemotherapy-induced Nausea and Vomiting
Lorazepam also has been used alone, but usually in combination with other drugs, such as 5-HT3 receptor antagonists, and/or corticosteroids, for the management of nausea and vomiting associated with emetogenic cancer chemotherapy, including that associated with cisplatin.
Lorazepam also has been used in the management of delirium. Results of several open studies suggest that combined therapy with IV lorazepam and IV haloperidol was more effective than IV haloperidol alone, with a shorter duration of delirium during combined therapy and fewer extrapyramidal manifestations. If a benzodiazepine is used for the treatment of delirium, those with a short duration and no active metabolites (e.g., lorazepam) are preferred.
Drug-induced Cardiovascular Emergencies
Lorazepam has been used adjunctively in the management of certain drug-induced cardiovascular emergencies and cocaine-induced acute coronary syndrome.