is one of the few treatments to actually regrow hair.
Unfortunately, it's expensive. The way to get it cheaper is to ask your MD for a prescription for generic Proscar. Proscar is Propecia, but intended to treat benign prostatic hyperplasia.
It comes in 5mg tablets, but you can use a pill cutter to cut them into halves or more. (Fifths, to equal the dosage in Propecia, but even 5mg is safe.)
This is not medical advice. Talk to your MD before doing this.