Before you take two of anything, make sure you're acting on doctor's orders experts say. In the wake of Heath Ledger's death by accidental overdose, USA Today probes the dangers of polypharmacy, or taking multiple drugs at once. "It's extraordinarily dangerous for people to try to self-medicate," says a DEA spokeswoman. "It's like having a loaded gun."
Doctors and pharmacists should be able to head off harmful interactions, but patients sometimes get prescriptions from different places. "Certainly, there are less-scrupulous doctors who will prescribe in patterns not healthy for patients," says a pharmacology professor. "But sometimes the left hand doesn't know what the right hand is doing."