Ever since the federal Food and Drug Administration (FDA) approved the use of generic drugs in 1984, the controversy over whether they are just as good as the brand-name drugs that they were designed to mimic has not been resolved. Generic drugs contain the same amount of the same active ingredient as the brand name equivalent, but they may use different binders and inactive ingredients and be manufactured in different ways. The FDA’s requirement of “bioequivalency” requires that they contain the same amount of the active ingredient, and that patients should show similar levels of the drug in their blood.

Generic prescription drugs save American patients and their insurance companies some $200 billion dollars a year, and eighty percent of prescriptions are now filled with generic drugs. Drugstore shelves are also filled with generics next to their patented counterparts, with the generics’ labels inviting consumers to “compare” the store brand to the drug that they have taken since childhood, at a fraction of the price of the original drug. But thirty years after the first generic substitutes were approved by the FDA, many doctors still question whether generics really work as well as their original counterparts. In some cases, there is little doubt that switching can be dangerous for patients.

A long-time proponent of generic drugs now advises caution

Pharmacologist Joe Graedon, the author of the best-selling “The People’s Pharmacy” and the host of a popular radio show, was forced to examine his long-standing support for generics after he was contacted by Robin Lynn. In 2007, Lynn had been taking Wellbutrin XL, a long-acting version of a popular antidepressant when her doctor wrote her a prescription for a generic instead. At first, Lynn thought nothing of the change, but after a period of time she realized that her medication was not working as well as it did previously. She also felt as if she had received “a shot of adrenaline” when she took her pill each morning.

Graedon began to hear similar stories from hundreds of other patients who had switched from Wellbutrin XL and had experienced similar side effects and loss of efficacy. He contacted the FDA and asked them to investigate, but the agency did not respond. So Graedon brought the generic version to ConsumerLab.com, which independently tests generic drugs for universities, hospitals, government agencies and other clients. Graedon asked the lab to research how the generic drug dissolved, and whether it dissolved in the same way that the brand-name drug did.

When bioequivalency is a myth

The results were shocking. After two hours, 34 percent of the active ingredient had already dissolved. Wellbutrin XL pills had only released 8 percent of the ingredient in the same amount of time. This means that patients were getting a jolt of the medication, and could easily explain the complaints about jitteriness and insomnia. It would also mean that patients were getting a much lower amount of the drug later in the day, which could account for the patients’ perception that the drug was no longer working.

Trusting the FDA’s data

When Graedon confronted the FDA with his results, the agency did not want to discuss the results of its own tests. Finally, the agency had a confession to make – it had actually never tested this particular generic formulation in humans at all. Although the package insert stated that “equivalence had been demonstrated” in a study in patients, in fact the FDA had never tested the drug in humans at this dosage. It had relied on tests on a lower dose to “prove” that the higher dose generic was safe to use. The FDA’s rationale was bizarre: The higher dose had shown a risk of causing seizures, and the agency was not sure that it was ethical to test the drug in healthy volunteers. Seven years after it was approved, the generic version was taken off the market in 2012. (There are other generic versions of Wellbutrin XL still on the market, and none of them have the same problem). Graedon still believes that most generics are safe, but he now believes that there are dozens, if not hundreds, of generic drugs that are not bioequivalent as they are currently formulated.

You should always ask your doctor about any changes in your prescriptions, and call back promptly if you notice any changes in how you feel on the new drug. If you or a family member switched from a brand-name drug and noticed any change in your health, you should consult your doctor immediately. You should also consult with an attorney who is familiar with the complicated laws that govern prescription drugs. Saving a few dollars is never a good reason to take chances with your health.