Anticonvulsant Effect of the Aqueous Extract and Essential Oil of Carum Carvi L. Seeds in a Pentylenetetrazol Model of Seizure in Mice

BACKGROUND: Carum carvi L. (caraway), known as black zeera in Iran, has been indicated for the treatment of epilepsy in Iranian folk medicine. This study evaluated whether the aqueous extract and essential oil of caraway seeds have anticonvulsant effects in mice. METHODS: The anticonvulsant effects of the aqueous extract (200, 400, 800, 1600, and 3200 mg/kg, i.p.) and essential oil (25, 50, 100, 200, and 400 mg/kg, i.p.) of caraway were assessed using pentylenetetrazol (PTZ; 95 mg/kg i.p.) induced convulsions. Diazepam (3 mg/kg) was used as positive control. The latency time before the onset of myoclonic, clonic, and tonic convulsions and the percentage of mortality were recorded. In addition, the effect of caraway on neuromuscular coordination was evaluated using the rotarod performance test. RESULTS: The extract and essential oil dose-dependently increased the latency time to the onset of myoclonic (ED50, 1257 and 62.2 mg/kg, respectively) and clonic (ED50, 929 and 42.3 mg/kg, respectively) seizures. The extract and essential oil of caraway prevented the animals from tonic seizure with ED50s of 2142.4 and 97.6 mg/kg, respectively. The extract and essential oil of caraway protected 28.6 and 71.4% of the animals from PTZ-induced death, respectively, and had no significant effect on neuromuscular coordination. CONCLUSION: This study showed that the aqueous extract and essential oil of caraway had anticonvulsant properties. However, the essential oil was more potent and effective than was the aqueous extract as an anticonvulsant. Additionally, the anticonvulsant effect of caraway was not due to a muscle relaxant activity. These findings support the acclaimed antiepileptic effect of caraway in folk medicine and propose its potential use in petit mal seizure in humans.