Shouldn’t I Take Propecia Twice a Day?

Dr. Rassman,

Why is it not necessary to take propecia more often than once a day??? If I take 1mg at 6am, then 12 hours later, I only have 0.125mg in my bloodstream which has to last me another 12 hours. Since 0.125mg doesn’t block hair loss—aren’t I losing hair for the second half of the day??????

The studies done by the drug company for the FDA showed that the value of the 1mg daily dose was as good as twice the dose. The goal was hair counts, and the benefit on hair count was the same for 1mg as it was for 2mg.