We report two cases of a singular side effect induced by clomipramine, one in a man, the other in a woman (both patients were beninese). This consisted of the occurring of the association of very frequent yawning and sexual excitation (sexual excitation with vaginal lubrification for the woman and hypogastric feeling of sexual pleasure for the man). It appeared after a few days of ambulatory treatment of a depression with clomipramine 75 mg/day. Clomipramine and demethylclomipramine blood levels were respectively 85 and 95 ng/ml and 70 and 80 ng/ml for the two patients. Three similar cases had been reported in the literature with this same tricyclic antidepressant. Recently a first case has been reported with fluoxetin. On this basis, it could be suggested that serotoninergic mechanisms are involved in the development of such clinical manifestations. But it seems reasonable to consider that serotoninergic mechanism could interact with a dopaminergic one. In favour of this hypothesis is the implication of dopaminergic mechanisms in yawning in man or in the association yawning--penile erections in the rat. Some others clinical arguments are discussed.