BACKGROUND: In vitro studies reported the antifungal activity of Zingiber officinale (ginger) rhizome extract against certain dermatophytes and Candida albicans. However, no in vivo studies had been made.
OBJECTIVES: (1) To determine in vitro the antifungal activity of commercially prepared ginger rhizome powder against common dermatophytes and Candida albicans.
(2) To determine the Minimum Inhibitory Concentration (MIC) of commercially prepared ginger rhizome powder against Trichophyton rubrum and Candida albicans.
(3) To compare the efficacy and safety of ginger 25 mg/g cream versus ketoconazole (Nizoral) 20mg/g cream on patients with tinea.
METHODS: Patients (n=24) with tinea corporis or tinea cruris were randomly allocated to two groups. They were instructed to apply either ginger or ketoconazole cream twice daily on lesions for eight weeks. Follow-up consultations were done every two weeks for a total of eight weeks. Photographs, KOH and recording of parameters (erythema, papules, scaling and pruritus) per lesion were used as outcome measures. An investigator's global response assessment was done at the end to determine the improvement of each lesion.
RESULTS: The disk diffusion method revealed that Trichophyton mentagrophytes,Trichophyton rubrum and Candida albicans were inhibited by the ginger powder at 2 mg/10?L. The MIC for C. albicans as 12.5 mg/ml and 25 mg/ml for T. rubrum. The age, gender distribution, and the severity index of the two treatment groups were comparable at baseline. There were significant improvements in erythema, papules, pruritus and scaling scores of patients in each group across different time points (Friedman's ANOVA p<0.05), with significant differences between the two groups noted during the initial observation periods (Wilcoxon p50% and >95% conversion rate to negative KOH at the fourth and eighth week of treatment for the ginger group respectively, while 100% conversion to negative KOH was noted at the second week of treatment for ketoconazole. One patient in the ginger group experienced increased erythema, pruritus and thickness of her lesions during the second week of treatment and the medication was discontinued.
CONCLUSION: While ketaconazole 20mg/g cream treatment resulted in faster clearance of fungal lesions, ginger 25mg/g cream yielded progressive improvement of tinea corporis and tinea cruris when used over an eight week period. Ginger cream may be an affordable alternative antifungal treatment. Future studies using a higher concentration and larger sample size are recommended although a possible case of contact dermatitis is seen using 25mg/g ginger cream.