Random pharmacy facts I learned today

• Given orally, diphenhydramine (Benadryl) is an antihistamine, i.e. it blocks the signal that causes inflammation when you have, for example, an allergic reaction. Applied topically, I always assumed it did the same thing. It does not. Topically it is an analgesic (pain reliever) and nothing more.
• I knew you shouldn't give "baby aspirin" to a baby, but I didn't realize, you should never treat a baby with "baby powder". Stick with zinc oxide.
• Heroin use is not glamorous. After watching a documentary of people saying they'd only smoke it never inject it, then nine months later watching them inject it into their necks since they ran out of other spots, was somewhat disconcerting. Oh, and out of the five people we started watching, three turned to prostitution (1 girl, 2 guys) and ended up HIV positive.