switching from fin/minoxil to prp

[M7md]

I have been on fin/minoxil on and off for a year - now seven consecutive months . the results I got so far are not satisfying , only some fine hair has grown on the temples and the crown . besides I'm so concerned about the side effects of finastride specially that it could cause cancer so I've decided to continue using prp only .
I can imagine that there're many others who switched from finastride and minoxil to prp and I was wondering , will I start shedding again till the prp starts to work ( the doctor explained to me that I will see the results in three months ) ?
will I lose the fine hair I got using the previous medications first or will I be able to keep them ?
I'm planning on a sessions every month and I hope it won't be just a waste of time .