Citalopram in PMS patients with prior SSRI treatment failure: a preliminary study.

Abstract

OBJECTIVES Evidence shows that the selective serotonin reuptake inhibitors (SSRIs) effectively reduce the symptoms of severe premenstrual syndrome (PMS). A placebo-controlled study of citalopram, the most selective SSRI, demonstrated that half-cycle dosing (luteal phase) was effective for DSM-IV-defined premenstrual dysphoric disorder (PMDD), a severe form of PMS. This study examined the effectiveness of half-cycle dosing of citalopram in PMS patients who did not respond to previous SSRI treatment. METHODS Seventeen women with no improvement in symptoms after two menstrual cycles on an SSRI were given open-label citalopram (20-40 mg/day). Eleven subjects received half-cycle dosing, and 6 subjects received full-cycle dosing. Scores on the 17-item daily symptom report (DSR) and on each of five DSR symptom clusters were used to measure citalopram efficacy. RESULTS Total premenstrual DSR scores were significantly improved (p <0.001) in both half-cycle and full-cycle dosing groups. The half-cycle group reported lower DSR scores throughout treatment compared with the full-cycle group, but the difference did not reach statistical significance in this small sample. All DSR factor scores (mood, behavioral, pain, physical symptoms, and appetite) significantly improved. Clinical improvement (>or=50% decrease from baseline DSR) was reported by 76% of the subjects overall. Forty-one percent of the subjects experienced symptom remission, defined as a decrease in symptoms to postmenstrual levels. CONCLUSIONS These results from a small number of subjects with open-label treatment must be viewed as preliminary but suggest that citalopram treatment is effective for PMS patients who failed previous SSRI treatment.