I know that 99.9% isopropyl alcohol is the preferred type for making finasol; however, the drug store by my house only has 70% and 91%. Will 91% work? Anyone with thoughts/answers to this please post.
I think the reason for the high alcohol content is that alcohol magically disappears. Using anything less then the recommended, will leave other undesired trace elements hanging out. Sure it will work, might not be healthy tho. You probably want input from someone that has tried it, so I'll shut up.
The effectiveness of 91% isopropyl Alcohol will be significantly less then 99%. The high percentage is important to maximize the lipophic properties of the isopropyl alcohol.
It's possible the water could help with the moisture in the skin which is important for in applying transdermal drugs. But there's no evidence this helps with Finasol.