Description
Pagoclone is a new cyclopyrrolone partial agonist. In animal models of antianxiety activity, pagoclone is more potent than benzodiazepines, is less sedating, and has a high therapeutic index (Table 29–1). In clinical studies, pagoclone is well tolerated and does not appear to cause sedation or affect psychomotor or cognitive performance. In studies of volunteers, it has been shown that it does not cause withdrawal symptoms on abrupt discontinuation after 14 days. These factors all suggest that pagoclone may be an important drug for the future. It is currently entering dose-ranging and comparative studies involving patients with anxiety disorders, and in a pilot crossover study, it reduced panic attacks; adverse effects were not different from or more numerous than those reported with placebo (Sandford et al. 1998).
Side effects
Pagoclone is a novel cyclopyrrolone that acts as a partial GABAA receptor agonist. Preclinical studies suggest that pagoclone may have clinical utility as an anxiolytic agent, as well as a reduced incidence of side-effects. Pagoclone differs from benzodiazepines in that it does not emit a full electrophysiological response to GABA stimulation in vitro. Adverse events appear to be dose-related, with the most common side-effects reported as somnolence, dizziness, headache, asthenia, and lethargy, though cognitive effects have not yet been tested.
