Proconvulsant and convulsant effects of cocaine have been described in various experimental models of epilepsy. We have studied the susceptibility to bicuculline and pentylenetetrazol-induced seizures in developing 10-, 20- and 30-day old rats, gestationally exposed to cocaine. Incidence and latency of appearance of the epileptic manifestations, their evolution toward status epilepticus and successive recovery or death, have been evaluated and compared to the same parameters obtained in control animals of the same ages. Results have demonstrated that 10-day-old rats that had been exposed to cocaine are significantly less sensitive than control animals to the convulsant action of both bicuculline and pentylenetetrazole while no substantial differences between the two groups have been found at the successive ages. It is possible that modifications of various neurotransmitter systems caused by prenatal cocaine exposure modify neuronal excitability at least at early stages of development.