Topical minoxidil (MNX) is well known for treating alopecia and it is reported that about half of the androgenic alopecia patients is effective. However, little has been known about dose-response profile of topical MNX in clinical setting.
The purpose of this study is to determine the relationship between the total amount of topical 3% MNX applied and its clinical response.
24 Korean patients with androgenetic alopecia were enrolled, instructed using distributed 3% MNX twice daily for 24 weeks. MNX bottles were collected at 12 weeks and 24 weeks, and remaining amount was measured to calculate the amount of MNX used. Then, the amount of MNX used and efficacy parameters like changes in hair density or mean hair diameter were compared.
At initial visits, mean hair density was 113±32 /cm2, and hair thickness was 45±14 ㎛. After 24 weeks, hair density was increased to 128±36 /cm2, and hair thickness was also increased to 49±15 ㎛. The mean total amount of MNX used for 24 weeks was 168±53 ml, which is much less than recommended dose. The amount of MNX used and the change of hair density were directly proportional (r=0.639, p<0.001), also there was a linear correlation between the change of hair thickness and the amount of MNX used (r=0.51, p<0.02).
Thus, the dose of MNX used is very important determinant for good result, therefore doctors and pharmaceutical companies must make every effort to enhance patient’s compliance.