Baclofen exacerbates epileptic myoclonus in kindled rats

Electrically kindled rats exhibit myoclonic jerks (1-25/min for 30-90 min) when injected with 200 mg/kg i.p. cysteamine. L-Baclofen, 10 mg/kg i.p. injected 45 min prior was not anticonvulsant but rather exacerbated the myoclonus. Furthermore, baclofen itself induced myoclonus in 29% of kindled rats at 10 mg/kg and in 100% of kindled rats at 15 mg/kg. These findings suggest that caution should be exercised before proposing the use of baclofen as an anticonvulsant or indeed using baclofen in patients who are predisposed to seizures.