Q: Hey doc, you told me to cut up 5mg finasteride into four parts. Why not five, so that it will be equal to Propecia which is 1mg? — H.F., Eastchester, NY

A: For several reasons:

1) you will lose some of the medication in the cutting process,
2) the generic dose can be slightly less than the brand, and
3) it is too difficult to cut into five parts – four is hard enough.

Note that due to the fact that finasteride stays in the hair follicle for a long time, the pieces do not have to be in four equal parts.