5% Minoxidil lotion was approved for using to stimulate hair growth in male androgenetic alopecia by US FDA science 1988. The mechanism of action still unclear. In general the 5% Minoxidil in solution is the first choice preparation for treatment, therefore allergic contact dermatitis to solution was report up to 5.7% (Ebner H. et al,1995). Propylene glycol which is the main solvent of these solution, was the main responsible to allergic contact dermatitis with positive patch test up to 81.8% (Friedman ES. et al. 2002) One of the alternative solution using butylene glycol as the solvent was invented to solve the problem. In Siriraj hospital the investigators using this new solvent and made our in house product called 5% Minoxidil milky lotion. However the efficacy and safety of the new solution have not been investigated. This study is conducted to evaluated efficacy and safety of 5% Minoxidil milky lotion compare with the classic solution in male androgenetic alopecia.

The 5% Minoxidil in solution is the first choice preparation for treatment for Androgenetic Alopecia (AGA), 5% Minoxidil milky lotion is the alternative solution using butylene glycol as the solvent to solve allergic contact dermatitis problem. In Siriraj hospital the investigators using this new solvent and made our in house product called he efficacy and safety of the new solution have not been investigated. This study is conducted to evaluated efficacy and safety of 5% Minoxidil milky lotion compare with the classic solution in male androgenetic alopecia.

Inclusion Criteria:

• New case male AGA
• Classification Norwood III vertex or IV

Exclusion Criteria:

• Have previous AGA treatment in 6 month prior
• Complicated case with other disease condition effect hair such as Anemia, DM, Chronic alcoholism, Autoimmune disease, Thyroid disease, previous GI surgery etc.
• Other scalp lesion such as Psoriasis, Tinea capsitis
• Psychological disorder including trichotillomania