Safe and Effective Management of Tinea Cruris with Rhinacanthus nasutus Root Extract Gel (0.2% Rhinacanthin C): A Case Report on Clinical and Mycological Outcomes

Abstract

Tinea cruris is a dermatophyte infection affecting the genital area, groin, buttocks, and inner         thighs, commonly presenting with erythema, desquamation, pruritus, and a burning sensation. While antifungal medications are standard treatments, resistance and recurrence are increasing concerns. In Thai traditional medicine, herbal remedies are also considered for the treatment of fungal skin diseases. This case report described the management of tinea cruris in a 23-year-old male patient who had been suffering from the condition for one year. The patient had previously been treated with ketoconazole cream for 5-6 months, followed by a topical steroid with anti-inflammatory, antibacterial, and antifungal properties for one month. Although itching improved, the lesions persisted and worsened after treatment stopped. Microscopic examination using KOH preparation revealed septate hyphae with arthroconidia from the skin lesion. The patient was then treated with Rhinacanthus nasutus root extract gel (0.2% rhinacanthin C), applied to the affected areas twice daily for eight weeks. Clinical improvement was observed within two weeks of treatment initiation, and KOH preparations remained negative from the second week through the end of the treatment period. The patient tolerated the herbal gel well, with no adverse effects reported. There was no recurrence of tinea cruris during one year of follow-up. This case report suggests that R. nasutus root extract gel, containing 0.2% rhinacanthin C, was effective in relieving both the clinical symptoms and mycological aspects of dermatophytosis. The gel formulation may be a safe and effective topical alternative for the management of tinea cruris.