very preceptive of you to notice this "inconsistency." olivia and ther other posesters have provided you with excellent information.
now i would like to present my more cynical view. all medications are actually poisons which affect erery cell in your body. no poison attacks only one thing, or, if it does, it affects that one thing which causes other things to happen. sometimes the drug companies find a poison with a side effect that is considered "beneficial," the other side effects don't go away. that's why a drug first used for one illness is used for another illness. initially, prescriotions for the "secondary" side effect are "off the label." a drug rep convionves a dr to try the drug for an illness not listed on the label of the drug. the more side effects teh drug companies can use for a drug, the more the drug is prescribed, and the more money the drug companies make. nothing wrong with that unless one of the other side effects is heart failure or cancer.
the fda must approve all uses of a drug, so "off the label" prescriptions are on the head of the dr. of course, you must remember that about 80% of the fda's budget comes from pharmasudiocal companies and that many heads of fda departments are often hiored at obscene salaries by pharmasudical companies.
we are well looked afer. the best government money can buy.
That light at the end of he tunnel? It's an on-coming train.