CYP3A4 isozymes are necessary in order for finasteride to be metabolized. Could some sort of CYP3A4 isozyme defiency then maybe be the source of the problems?
connection.lww.com/products/foye … eRA-06.asp
“Whereas no clinically significant drug interactions have been reported, CYP3A4 inhibitors appear to have the potential for affecting the activity of finasteride.”
ncbi.nlm.nih.gov/entrez/quer … t=Abstract
Apparently grapefruit juice, to name one example, contains potent CYP3A4 inhibitors, which would act to prevent circulating finasteride from being metabolized…