Forty-five cases of ciguatera poisoning in Puerto Rico (P.R.) are described. These cases represent all those reported to the P.R. Poison Control Center in 1982. Most of the cases were reported in the spring and summer months. The most common fish ingested was the grouper. The clinical presentation of acute and long term symptoms was similar to that reported in other geographical areas, except the incidence of paresthesias. Paresthesias were reported in 11% of the patients reported to the poison center. A companion telephone survey indicated that persons in P.R. that do not eat fish do so because of fear of ingesting the toxin. Our findings indicate an overall familial contact with the ciguatera toxin in Puerto Rico at 7%. This study is the first to document that ciguatera is a common poisoning reported to the Poison Control Center in Puerto Rico. Our findings also support other authors contentions of geographical variations in clinical symptomatology.