Sumac (Rhus coriaria L.) Capsules for the management of hypermenorrhea: Protocol for a randomized triple-blind trial

Background Hypermenorrhea is a common gynecological disorder adversely affecting women’s quality of life. Conventional treatments, particularly hormonal therapies, are associated with side effects and contraindications. Rhus coriaria L. (sumac) has a historical basis in Persian medicine for its astringent and haemostatic properties, supported by modern phytochemical evidence of tannins and flavonoids. However, robust clinical evidence for its efficacy in hypermenorrhea is lacking. This study aims to evaluate the efficacy and safety of sumac capsules compared to a placebo in reducing menstrual blood loss in women with hypermenorrhea. Methods A triple-blind, parallel-group, randomized, placebo-controlled clinical trial will be conducted. Sixty eligible women aged 18–45 years with hypermenorrhea (Pictorial Blood Loss Assessment Chart [PBAC] score ≥100) will be randomly allocated to either the intervention group (500 mg sumac capsule twice daily for the first 7 days of menstruation) or the control group (Avicel placebo capsule), over three consecutive menstrual cycles. Discussion This protocol details a methodologically rigorous trial to generate high-level evidence on the potential of sumac as a complementary treatment for hypermenorrhea. If proven effective, sumac could offer a safe, accessible, and cost-effective therapeutic alternative, aligning with patient preferences for natural interventions. The results will inform future clinical practice and research in integrative women’s health. Trial registration Iranian Registry of Clinical Trials (IRCT), IRCT20180218038783N12 , registered on 5 October 2025.