Comparative study of 5% and 2.5% potassium hydroxide solution for molluscum contagiosum in children

Molluscum contagiosum (MC) is a pediatric viral infection that is fairly contagious. Although various treatment methods are available, the presence of facial lesions limits options of therapy.

We aimed to test an alternative treatment consisting of application of two different concentrations of potassium hydroxide (of KOH 5% solution and of KOH 2.5% solution) aqueous solution.

In this study we evaluated the effectiveness and side-effects of daily applications of potassium hydroxide (KOH) aqueous solution at 2.5% and 5% concentrations, twice daily in 29 children with MC. Out of a total of 29 patients with molluscum contagiosum included in the study, 13 patients in the 2.5% KOH group and 12 patients in the KOH 5% group completed the study. Families were instructed to apply potassium hydroxide twice a day. The assessment of response and side-effects were performed on days 0, 15, 30, 45 and 60 (visits were numbered 1, 2, 3, 4 and 5, respectively) and one month after.

We had a total of 11 (44%) patients who completely recovered after the fifth visit. While eight (66.7%) of these 11 patients were in the 5% treatment group, three (23.1%) patients were in the 2.5% treatment group, and there was a statistically meaningful difference (p < 0.047). Patients with fewer lesions remitted better (p < 0.05). When number of lesions were taken into consideration, difference between the two treatment groups appeared after the fourth visit (p < 0.001). There were no statistical differences between the two groups with respect to side-effects (p = 0.682).

Potassium hydroxide solution at a concentration of 5% was more effective than 2.5% in our patients. The treatment was well-tolerated on the face with the advantage of administration of lower concentrations. This study suggests potassium hydroxide may be a more preferable mode of treatment for molluscum contagiosum lesions on the face.