a double blind randomized trial of efficacy and safety of 5% methimazole versus 2% hydroquinone in patients with melasma

Background: melasma is an acquired facial hyperpigmentation that is chronic and resistant to treatment. this study aimed at comparing the therapeutic response and safety of 5% methimazole cream versus 2% hydroquinone cream in iranian females with melasma. methods: this was a randomized, controlled, double-blind clinical trial. fifty-eight patients aged 18 to 50, and who had been clinically diagnosed with melasma were enrolled. they were randomly divided to 2 groups: those treated with 5% methimazole cream and those treated with 2% hydroquinone once nightly for 8 weeks. their responses to treatment were evaluated using the melasma area and severity index (masi), the δ e score obtained using visioface digital photography, and the patients’ ownsatisfaction. safety wasassessed by measuring thyroid-stimulatinghormone(tsh) levels. for statistical analysis, the spss version 16.0 forwindows(spss inc., chicago, il) was used. results: the subjective assessments of methimazole and hydroquinone (patient satisfaction) were as follows: excellent and good, 67.7% for methimazole vs. 70.3% for hydroquinone, and moderate and mild, 32.2% for methimazole versus 29.6% for hydroquinone. the assessments showed no statistical differences between the 2 groups (p = 0.942). at the end of treatment, masi scores were significantly lower in the methimazole group than in the hydroquinone group (p = 0.042). the visioface
e scores were also significantly lower in the methimazole group than in the hydroquinone group (p = 0.049). serum thyroid stimulating hormone (tsh) levels showed no statistical differences between the 2 groups (p = 0.613). conclusions: compared with 2% hydroquinone, topical methimazole was more effective for improving melasma and had no effect on serum tsh levels. therefore, methimazole could be considered as a first-line or combination therapy for melasma.