Note that generics are not identical to branded drugs; I believe the FDA has a +/-20% bioavailability tolerance. For medications with broad dose-response curve

Note that generics are not identical to branded drugs; I believe the FDA has a +/-20% bioavailability tolerance. For medications with broad dose-response curves (e.g. most painkillers, probably lots of other classes of drugs) this isn't a big deal, but for other medications it can be. As I understand it, psychiatric medications often have narrower dose-response curves (disclaimer - IANAD).