Sandmac the body is a complicated thing.
Ive often wondered why some folk manage the meds well when others do not.
I would say it wont harm you any by reducing the dose to a level that suits you.
This could be 1/4 daily ,1mg every 2 or 3 days and even 1mg once a week.
Once you get a level which seems SIDES free only time will tell if it has positive effect on maintaining your hair.