Question: 5mg oral minoxidil once a day or 2.5mg oral minoxidil twice a day, which would yield better results?
The issue at hand is not the blood levels achieved. A dose of 5mgs runs heart risks not worth taking for a healthy man. The point is at what level will the hair effect happen. The answer is a 2.5mgs daily, good results are seen and it is safe from severe cardiac side effects.