(HealthDay)—Once-daily capsules containing a combination of minoxidil and spironolactone appear to be safe and effective for the treatment of female pattern hair loss (PHL), according to a case-series study published online Dec. 12 in the International Journal of Dermatology.

Rodney D. Sinclair, M.B.B.S., M.D., from Epworth Hospital in East Melbourne, Australia, presents a case series of 100 women with PHL treated with once-daily minoxidil 0.25 mg and spironolactone 25 mg. Shedding and hair density were scored before and after 12 of treatment.

Sinclair observed a 0.85 mean reduction in severity score at six months and a 1.3 mean reduction at 12 months. There was also a mean reduction of 2.3 in hair shedding score at six months and a mean reduction of 2.6 at 12 months. There was a drop in blood pressure observed among participants (mean change, −4.52 mm Hg systolic and −6.48 mm Hg diastolic). Eight women experienced side effects, which were generally mild, although two who developed urticaria discontinued treatment. No cases of hyperkalemia or any other blood test abnormality were reported.

"Most noticed a reduction in hair shedding at three months and an increase in density at six months," Sinclair writes. "Placebo-controlled studies to investigate this further are warranted."

Sinclair discloses holding a related innovation patent.