Discontinuation of Clonazepam in the Treatment of Social Phobia

Abstract

Patients with social phobia who responded well to 6 months of open-label treatment with clonazepam were assigned to receive either continuation treatment (CT) with clonazepam for another 5 months, or to undergo discontinuation treatment (DT) using a clonazepam taper at the rate of 0.25 mg every 2 weeks, with double-blind placebo substitution. Clinical efficacy was compared between the CT and DT groups using three different social phobia scales. Benzodiazepine withdrawal symptoms were also measured. Relapse rates were 0 and 21.1% in the CT and DT groups, respectively. Subjects in the CT group generally showed a more favorable clinical response at midpoint and/or endpoint, although even in the DT group clinical response remained good. With respect to withdrawal symptoms, the rates were low in both groups (12.5% for CT and 27.7% for DT) with no real evidence suggesting significant withdrawal difficulties. At the end of 11 months of treatment with clonazepam, however, a more rapid withdrawal rate was associated with greater distress. This study offers preliminary evidence to suggest that continuation therapy with clonazepam in the treatment of social phobia is safe and effective, producing a somewhat greater clinical benefit than a slow-taper discontinuation regime. However, even in the DT group, withdrawal symptoms were not found to be a major problem. The study can be taken as supportive of benefit for longterm clonazepam treatment in social phobia, as well as being compatible with a reasonably good outcome after short-term treatment and slow taper.

Social Phobia: Issues in Assessment and Management

“…Early and robust effects were seen with this drug. In a long-term discontinuation study with clonazepam, patients who received maintenance therapy with the drug for 12 months did better than those who went into a slow discontinuation at 6 months (27). These findings demonstrate that benzodiazepines can clearly be useful, particularly clonazepam.…”

Management of anxiety disorders: The added challenge of comorbidity

“…Open studies have reported that alprazolam and clonazepam are effective in treating social anxiety disorder [Munjack et al, 1990;Ontiveros and Fontaine 1990;Reiter et al, 1990;Reich et al, 1989;Lydiard et al, 1988], as have a few controlled trials [Davidson et al, 1993b;Connor et al, 1998;Gelernter et al, 1991]. A placebo-controlled study in 75 patients with social anxiety disorder reported a response rate approaching 80% for patients on clonazepam compared with 20% for the control group [Davidson et al, 1993b].…”

Issues and controversies surrounding the diagnosis and treatment of social anxiety disorder

“…However, some evidence suggests that this may not be the case. For example, Connor et al examined double-blind randomization to continuation of clonazepam versus discontinuation with placebo matching after 24 weeks of open-label treatment [112]. Although sample size was likely too small to compare relapse rates as a categorical variable (intent-to-treat sample size of 36), Review a Kaplan-Meier analysis showed that patients in the discontinuation condition exhibited a significantly shorter time to relapse compared with patients in the continuation condition.…”

“…Presence of withdrawal symptoms appeared to increase in the discontinuation condition during the taper period (from 6.7 to 27.8%), and there was a trend toward the discontinuation condition showing a greater number of withdrawal symptoms compared with the continuation condition at the midpoint of the taper period. Connor et al acknowledged that a limitation of their study was assessing withdrawal symptoms only 1 week after both groups had fully discontinued clonazepam [112]. It is important to assess this for a longer period of time, as a recent prospective study showed four different patterns of withdrawal symptoms (one of which included an increase in withdrawal symptoms 4 weeks after tapering was completed [113]).…”