The effects of low doses of lorazepam (Ativan), 0.03 mg/kg IV, on episodic versus long-term memory, attention, and somatic and affective symptoms were investigated in a group of 16 children aged 2.8 to 14.2 years at St. Jude Children’s Research Hospital, Memphis, and the Center for Pediatric Pharmacokinetics and Therapeutics, Departments of Clinical Pharmacy and Pediatrics, University of Tennessee, Memphis. Psychological assessments were performed twice before drug administration and 1½ hours and 24 hours after intravenous lorazepam. A selective anterograde amnestic effect was observed in 5 of 16 children as measured by a picture recognition test. There were no significant changes in long term memory, attention or somatic symptoms but affective symptoms were significantly decreased at 1½ hours and a trend toward decreased anxiety was seen at 1½ and 24 hours after lorazepam injection. The half life of lorazepam was 10.5 ± 2.9 hours. [1]

COMMENT. Lorazepam is a short acting benzodiazepine that is used in children most commonly as a preoperative sedative and as an anticonvulsant. In adults it is used as an antiemetic agent during chemotherapy for cancer, an effect largely due to its amnestic properties. This study shows that it is possible to produce a selective amnestic effect on episodic memory in children without significantly impairing long-term memory or attention.

Lorazepam has become increasingly popular for the treatment of status epilepticus in children; the usual median dose is 0.1 mg/kg. Midazolam, a benzodiazepine used primarily for induction of anesthesia, in contrast to lorazepam and diazepam, is water soluble and its injection is neither painful nor irritating by the intramuscular route. Midazolam 15 mg IM was as effective in abolishing spikes as 20 mg of diazepam IV five minutes after administration in a study in adults with epilepsy [2]. The half life of lorazepam is longer than that of diazepam or midazolam, however, and its duration of action is more prolonged.