It is possible that the antidepressant fluoxetine [‘Prozac’] will be approved in another indication, meaning that more patients could benefit from treatment with the drug. Canadian researchers have reported that fluoxetine is effective in women with premenstrual syndrome (PMS), particularly the most severe form of PMS, premenstrual dysphoric disorder (PMDD). It is estimated that 40% of European women regularly suffer moderate-to-severe PMS with symptoms ranging from breast tenderness and weight gain to depression, anxiety and even suicidality. Many treatment options have been suggested for women with PMS and PMDD, but currently there is no consistently effective solution. Therapies of the future should look towards the 5-HT (serotonin) neurotransmitter system, indicate results from 2 studies presented at the 21st Congress of the Collegium Internationale Neuropsychopharmacologicum (CINP) [Glasgow, Scotland; July 1998].