The testing helps to determine the medication's safety, side effects, and most effective dosage for its intended use. USP standards help to assure consistent potency and dosage of medications. The USP seal also indicates that the ingredients in the medication are exactly as stated on the label, and that the medication is pure and uncontaminated.
Actual results vary considerably from person to person.
Many people will not experience any benefits. Some will have a reduced degree of hair loss. Others will see a modest amount of regrowth. And some people will respond to certain pharmaceutical treatments with substantial regrowth of their own hair. When pharmaceutical treatments do have a positive effect, there is nothing artificial about the regrown hair and nothing to fall off.