Efficacy of 0.5 mg Dienogest Tablets in Treating Premenstrual Syndrome-like Symptoms: A Comparative Study with a Low-Dose Estrogen–Progestin Combination

Dysmenorrhea treatment with 0.5 mg dienogest tablets twice daily (1 mg/day) has proven useful, but its effect on premenstrual disorders has not yet been evaluated. This study aimed to evaluate the efficacy of 0.5 mg dienogest tablets in relieving premenstrual syndrome (PMS)-like symptoms during the treatment of dysmenorrhea in comparison with that of continuous low-dose estrogen–progestin (LEP/COC) drospirenone/ethinylestradiol combination, which is considered effective in treating premenstrual dysphoric disorder. During the standard course of dysmenorrhea treatment with dienogest or LEP/COC, PMS-like symptoms were scored based on patients’ reports, and the treatment effects were compared. As a result, the dienogest group experienced a significant improvement in PMS-like symptoms compared with the LEP/COC group over the 6-month study period (p < 0.01). Furthermore, dienogest was more effective in providing relief from PMS-like symptoms, with 89.7% of patients reporting a complete resolution of PMS-like symptoms at 6 months, compared with 47.1% in the LEP/COC group (p < 0.01). These results indicate that dienogest is effective in relieving PMS-like symptoms, similar to LEP/COC. Further studies are needed to determine whether 0.5 mg dienogest tablets, which are only available in Japan, are effective in treating premenstrual disorders diagnosed via standard methods.