Abstract
Gynecomastia (breast enlargement) is a side effect of neuroleptic antipsychotic drugs,
related to prolactin elevation caused by dopamine D2 receptor blockade (Richelson,
1996). The atypical antipsychotic risperidone is less likely to cause gynecomastia
at low doses (Casey, 1996). It can cause a dose-dependent increase in serum prolactin
concentration (Peuskens, 1995), by blocking dopamine D2 receptors {Richelson, 1996).
I would like to describe a patient who did not have gynecomastia with risperidone
at a dose of 3 mg/day, but had it when risperidone, at a dose of 0.5 mg/day, was combined
with fluoxetine. A MEDLINE search failed to find any reports about such an interaction.
