Generics not always the same

They are supposed to be identical in effect, but sometimes they aren't. [Link]

Over the past decade or so, public acceptance of generics has increased. Many people want to get the generic equivalent. But now there are questions about the validity of the testing done to ensure bioequivalence. As reported in the LA Times:

FDA standards for generics are questioned
By Melissa Healy, Los Angeles Times Staff Writer
March 17, 2008

In carrying out its mission to ensure that generic drugs are "the same medicine" with "the same results" as the pioneer drugs they follow, the Food and Drug Administration rigidly applies a standard of what is called "bioequivalence." Measured in laboratories and in simple, small-scale human trials, a generic must deliver the same active ingredient to the bloodstream of patients in virtually the same amount at virtually the same rate as the pioneer drug.

The FDA considers "bioequivalence" a good surrogate for "therapeutic equivalence" -- the equal ability of two drug formulations to ease symptoms or cure disease. Physicians and pharmacologists say that for some copycat drugs, showing bioequivalence to the original is not proof enough that the "same medicine" will yield "the same results."...

The authors point out that the testing done to ensure bioequivalence tends to be very limited: only a small population of persons are studied, and that population tends to be composed of young, healthy persons. Plus, a drug is considered to be satisfactorily bioequivalent if the absorption of the drug is within 80 to 125% of the original.

80% - 125% seems like a pretty broad range of effect.