Dipyrone, a novel anticonvulsant agent? Insights from three experimental epilepsy models.

Dipyrone, a non-steroidal anti-inflammatory agent, was anticonvulsant in three experimental epilepsy models. At a dose of 300 mg/kg i.p., dipyrone blocked the maximal hind limb extension in the electroshock model in Wistar rats, the tonic-clonic component of acute sound-induced seizures and the limbic component of audiogenic kindling in genetically susceptible Wistar-derived rats, all in 100% of the animals. In the electroshock model higher doses (400 and 500 mg/kg) were also effective but lower doses (100 and 200 mg/kg) were not. In this model dipyrone had no effect on the recovery of the righting reflex and intensified the postictal antinociception in a dose-dependent manner. Other non-steroidal anti-inflammatory agents such as indomethacin, diclofenac and aspirin had no anticonvulsant effect in the electroshock-induced seizures.