by Neil Bauman, Ph.D.
I am sometimes asked: “Are generic drugs the same as brand name drugs?”
The simple answer is “yes” and “no”. Let me explain.
To receive FDA approval, generic drugs must meet a variety of criteria, including:
- A generic drug must have the same active ingredient or ingredients as the brand-name drug.
- A generic drug must have the same strength as the brand-name drug.
- A generic drug must have the same route of delivery (oral, topical, injectable, etc.).
- A generic drug must have the same dosage form (capsule, tablet, etc.). (1)
When you look at this list, you might think it tells you all you need to know—that generic drugs are essentially identical to brand-name drugs, but this is not the case.
You need to understand that when the FDA says that the active ingredient needs to be the same in both generic and brand-name drugs, what it actually means is that the allowable amount of the active ingredient in the generic drug must be within 5% of what’s in the brand-name drug. Furthermore, the amount of the active ingredient in a generic drug that gets absorbed in your bloodstream needs to fall within 10% of what’s absorbed from the brand-name drug. Thus, a generic drug may be a bit stronger or weaker than a brand-name drug. “This means that when compared with a brand-name drug, you could potentially absorb 90% of the active ingredient in the generic drug…or 110% of it…or any amount in between.” (1)
Typically, having a little bit more or a little bit less of the active ingredient in your bloodstream usually doesn’t matter. It’s no big deal unless you are taking one of the few drugs that are considered critical-dose medications such as lithium. With those, you may need to stick with a brand-name drug.
The other thing to consider is that although the active ingredient(s) is the same in both brand-name and generic drugs, the inactive ingredients may be different.
Don’t let that term “inactive ingredient” fool you. This does not mean that it is not “active” or otherwise harmful, it simply means that it does not cause the desired therapeutic effect that the active ingredient does. Many inactive ingredients are NOT benign—they have their own side effects. Thus, when taking a generic drug rather than a brand-name drug, you could have different side effects caused by the different inactive ingredients.
(1) Generic Lipitor—What You Need to Know. Bottom Line’s Daily Health News. February 9, 2012