I'm no expert, and so far (knock on wood, could change at any second) I don't take drugs. But from the experiences of my relatives, I would say you should check with your doctor as well as the FDA. Here are a couple of links I found illuminating (and I hope someone with medical training will jump in and inform us all):
Worried about generics?
"The FDA inspects the nation's approximately 3,000 domestic drug plants about once every two and a half years, according to a U.S. Government Accountability Office report published in September 2008. But the agency inspects only about 8 percent of foreign facilities in a given year, so that it would take more than 13 years to get to that group of plants, the GAO estimates. Overseas plants make ingredients for generic and brand-name drugs. An FDA spokeswoman says that the agency's recently opened offices in India and China will "over time allow greater access for FDA inspections." The FDA is beginning to collaborate with European countries and Australia to share inspection responsibilities."
Johns Hopkins: Prescription Drugs on safety of generic drugs: Johns Hopkins Health Alerts
"Health insurers love generic drugs, because they cost less money than branded versions -- on average, 30 percent less. But there are some instances when your doctor may not think it’s a good idea to switch to a generic drug. This is often the case for medications that have a narrow therapeutic range (NTR). When you take an NTR drug, the most effective dose with the fewest side effects lies in a narrow range between too little and too much. These are medications in which small changes in the dose and/or blood concentration could result in clinically important changes in drug efficacy or safety. Usually, these drugs require frequent adjustments in the dosage and the user needs to be monitored carefully, regardless of whether the drug is a brand-name or generic drug product."
So I personally would talk to my doctor as well as the FDA.