If I take Propecia on a Monday i.e. at 9 PM, and then take it on Tuesday at 11 AM, then I’ve taken Propecia both days. Is this an ideal scenario for getting the best results from the drug,
or should the times I take Propecia each day be separated by about 24 hours?

There is no point to do this. It probably does not make a difference. The drug has a half life of 5 hours or so, which means that in 24 hours, it is out of the blood stream. I usually tell people to take it in the morning when testosterone levels in men are the highest, but that is an intellectual analysis, not based upon any comparative study that I know of.

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