Am J Psychiatry 1988; 145:312-317
Copyright © 1988 by American Psychiatric Association
Clorazepate and lorazepam: clinical improvement and rebound anxiety
K Rickels, IL Fox, DJ Greenblatt, KR Sandler and A Schless
Department of Psychiatry, University of Pennsylvania, Philadelphia.
Sixty-two anxious patients were treated under double-blind conditions for 4
weeks with either clorazepate or lorazepam. Two-thirds of each treatment
group were then switched abruptly to placebo for 2 weeks, while one-third
continued to receive active medication. Two major findings were obtained.
About 70% of the patients maintained improvement during the 2-week placebo
period. Some patients, however, experienced rebound anxiety, which appeared
to be more intense and occurred earlier when placebo was substituted for a
benzodiazepine with a short half-life (lorazepam) than for one with a long
half-life (clorazepate). The clinical relevance of these findings is
discussed.
