Generic Drugs: Dos and Don'ts

Medically Reviewed by William Blahd, MD on July 27, 2016
4 min read

Trying to save money on your health care costs? "In general, generics are safe, a little bit less expensive, and mostly equally as effective to brand-name drugs," says John Meigs, MD, spokesman for the American Academy of Family Physicians.

Whether you're looking at over-the-counter products (perhaps a store brand of ibuprofen vs. Advil) or a prescription from a doctor, generic medications have the same active ingredients as brand-name drugs. But they're often much less expensive. Brand-name medicines are about five times more expensive than generic versions, according to the FDA.

"A brand-name drug that could be well over $100 may be as little as $5 as a generic," says Tod Cooperman, president of, an independent laboratory that tests supplements, medications, and health products.

But here's the catch: "They're not necessarily identical to the brand-name medication," Cooperman says. That's one of the things you'll need to consider when deciding whether to buy a generic or brand name.

A new medication goes through a lot of testing so the FDA can approve it. Then it's patented. That means the company who developed it is the only one who has the right to sell it for a period of time.

Once the patent expires, any company can apply with the FDA to sell their own generic version of that drug. That approval process isn't as complicated as it was for the original one.

The generic has to have the same active ingredients and in the same amount as the original. But the other ingredients in the pill, such as fillers, can be different. And that can affect how quickly the medication gets absorbed by your body, Cooperman explains.

The FDA allows a 15% difference, either more or less, in blood absorption for a generic compared to the original drug. One analysis of 2,000 studies found the average difference was about 3.5%. You can expect to get similar results when you compare generic and brand-name medicines as well as different batches of the brand name.

For some medicines though, small changes have a big impact in how your body responds and how well the drug works. What matters isn't necessarily the dose of the medication, but how much of it your body can use, Meigs says. With some conditions, a slight difference can have serious consequences.

Seizure medications are one example, he says. You can be taking the drug correctly, but your body may not get enough of it. And if the level of the drug in your blood goes too low, you could have a seizure.

"Patients who do well on one generic may not do as well on another generic," Cooperman says. "And the same goes for the brand-name medication vs. the generic."

Several different companies may make the same generic drug, too, but they might use different filler ingredients. So their medications could have slightly different rates of absorption or cause different side effects.

If you're happy with how a generic drug works for you, find out who the manufacturer is. Depending on the state you live in, this information might be on the prescription bottle. If it's not, ask your pharmacist to check. Then request that version every time you get your prescription filled.

Generics will usually be cheaper -- but not always, Meigs says. Competition between manufacturers drives down the cost of many. But sometimes, only one company is making a certain generic drug. Since they've cornered the market, they can hike up the cost.

And some generic drugs may not be covered by insurance. If the generic version of your prescription is too expensive for you, tell your doctor and your pharmacist.

Some pharmacies may offer specific generics at a cost that's even lower than your copay. To find out, ask directly: "What's the CVS price?" or "Is there a Walgreen's discount?"

"You might have to pay $10 a year for a discount card, but you can certainly get a pretty good discount that way," Cooperman says.

Paying out of pocket? You'll almost always be able to find the best deal at a wholesale club like Costco, he adds. "The way that the big retail pharmacies price their medications is that they mark it up significantly from the average wholesale price, which is already an inflated number," he says. "But Costco charges a lower markup, based on the amount they actually paid to get the drug."

If a generic drug doesn't work for you and insurance won't cover the brand-name version, you're not out of luck. Your doctor might be able to switch you to another medication.