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Is that generic really the same as your branded drug?

Medically reviewed by Drugs.com.

You’re at the pharmacy with a script from your doctor and you’ve been told you can choose between the brand-name drug and its generic equivalent. The difference in cost is significant. But does that equate to a difference in effectiveness or side effects?

Bringing a new drug to market costs over 2.6 billion dollars and patents on branded drugs allow companies up to 20 years to recoup most of those costs, if not more.

Once a patent expires, other companies can enter the market with a generic version produced for a much-reduced price because years have not been spent establishing safety or effectiveness. On average, generics are 80% cheaper than branded equivalents.

But does this mean that generics might possibly be less effective or safe? For 99% of all drugs, the answer is no. The exceptions are those with a narrow therapeutic index, such as carbamazepine, cyclosporine, digoxin, levothyroxine, lithium, phenytoin, tacrolimus, theophylline, and warfarin. With these drugs, small differences in dose or blood concentrations may have significant effects, and people taking these drugs should either stay with the branded version or transfer to one generic version that they like.

Theoretically, there may also be differences between controlled-release branded and generic formulations. When a patent expires, companies do not hand over a blueprint of their drug design to competitor companies, which means there may be variations in the delivery system of a drug. While this may mean differences in how fast or slow an active ingredient is released, the FDA still makes sure the total amount of drug released by a generic and its peak concentration are similar to the branded version. Studies have shown the actual variation is typically around 3.5%, and no different to that found when two batches of the same branded drug are tested.

The FDA expects all generic manufacturers to follow the same rigorous process. Sure, generics will always look different; the law prohibits two drugs from looking the same. Inactive ingredients, such as fillers, colors, and flavors, may also differ, but inactive means inactive and these rarely make any significant contribution to the way a drug behaves in the body.

Generic drugs save the U.S. healthcare system over $250 billion dollars every year. Opt for a generic and help keep healthcare costs and insurance premiums down.

To see if your branded drug has a generic equivalent or when its patent is due to expire see Generic Drugs – Availability and Patent Status

For more information see Generic Drug FAQs.

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