WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS
Concomitant use of ATIVAN and opioids may result in profound sedation, respiratory depression, coma, and death (see WARNINGS - Risks from concomitant use of opioids and benzodiazepines).
- Reserve concomitant prescribing of these drugs for use in patients for whom alternative treatment options are inadequate.
- Limit dosages and durations to the minimum required.
- Follow patients for signs and symptoms of respiratory depression and sedation.
Ativan (lorazepam) is an active benzodiazepine with a depressant action on the central nervous system. It has anxiolytic and sedative properties which are of value in the symptomatic relief of pathologic anxiety in patients with anxiety disorders giving rise to significant functional disability but is not considered indicated in the management of trait anxiety.
Ativan (lorazepam) has also been shown to possess anticonvulsant activity.
Lorazepam is rapidly absorbed after oral administration, with mean peak plasma concentrations of free lorazepam at 2 hours (range between 1-6 hours). Following intravenous administration, peak plasma levels are reached within minutes, whereas following administration by the intramuscular route, peak plasma levels occur between 60 to 90 minutes. After sublingual administration, peak plasma levels occur at 60 minutes. By the intramuscular route, the absorption half-life values of lorazepam average 12 and 19 minutes, whereas by the oral route, there is an additional lag period averaging 15 and 17 minutes. Bioavailability was shown to be identical by all routes of administration.
Lorazepam is rapidly conjugated to a glucuronide which has no demonstrable psychopharmacological activity and is excreted mainly in the urine. Very small amounts of other metabolites and their conjugates have been isolated from urine and plasma.
The serum half-life of lorazepam ranges between 12 to 15 hours, while that of the conjugate varied between 16 to 20 hours. Most of the drug (88%) is excreted in the urine, with 75% excreted as the glucuronide. At the clinically relevant concentrations, approximately 85% of lorazepam is bound to plasma proteins.
Anterograde amnesia, a lack of recall of events during period of drug action, has been reported and appears to be dose-related.