Generic Medications: The good and the bad (Part 1)

As noted in the February 2011 issue of Review of Optometry, patients are asking more often for generic medications instead of brand named drugs. A question one has to ask: “are generics as safe and effective as their branded counterparts?” Another question that needs to be asked: “are there any potentially negative outcomes through the use of these generics?

The level of use of generic alternatives in the US is one of the highest among developed nations. Not all drugs are equal, and there are pros and cons to using generic equivalents. The U.S. Food and Drug Administration (FDA) estimates that 7 out of 10 prescriptions written in the U.S. are for generic medications. Both Medicare and state Medicaid drug plans substitute generic drugs around 80% of the time if the generic version is available.

Let’s look at how a generic drug becomes available to the public. The generic counterpart of a branded drug becomes available for production when the patent expires, generally after 20 years. The FDA authorizes the production of that medications generic counterpart if bioequivalence can be demonstrated. This means that the active ingredient of the drug has to be released into the blood stream at essentially the same speed and in the same amount as the original drug.

With systemic drugs, a manufacturer can perform bioequivalence studies comparing the absorption, efficacy, and elimination of a systemic generic drug. This can be generally obtained by measuring levels of the drug in the blood stream after taking the drug. The concentration must be between 85% and 125% of that measured for the branded drug. Unfortunately, ophthalmic drugs can’t be compared this way. The only FDA regulation for ophthalmic medications requires the generic must contain the same concentration of active ingredient as the brand name product, as well as the dosage, form and route of administration. There could be potential differences in the amount of drug that gets into the eye when comparing a generic to a branded drug.

This entry was posted in Medications and tagged , , , , , . Bookmark the permalink.

Leave a Reply