wow, how did he change his appearance so much?
"Up-to 4 times more effective than a placebo in clinical testing"
Anyone considering hair loss medication should do some concerted research.
So tread carefully. The set of women who are sexually attracted to bald men is much, much larger than the set of women who are sexually attracted to men who are unable to have sex.
They're off-the-counter products, but you still might want to talk to your doctor about it, not because there are any significant side effects, but because it's a good habit.
"Sometimes patients given a placebo treatment will have a perceived or actual improvement in a medical condition, a phenomenon commonly called the placebo effect."
Here is one way that I think has a good chance of working: have your subjects pay a fairly steep amount for the trial, the evaluate it by having them fill in a questionnaire.
The "pay to take part" selects for gullibility, and also makes the subjects feel stupid if they don't report improvement. The "self-reporting", of course, helps get rid of such things as objective measurements that would spoil the party.
Finally, pick a small test group. That's cheaper, and will give positive results if only a few subjects report actual improvement. And if your first test fails, run a second, this, etc. identical test.