Generic Medications

Generic medications often are available at greatly reduced prices, relative to their branded counterparts.

What is a Generic Drug?

The active ingredient of a 'generic' medication is chemically identical to the active ingredient of the corresponding branded medication. Because they are often cheaper than their branded counterparts, many people choose generics, and many insurance companies actually require that they be used.

According to the FDA's Office of Generic Drugs:

A generic drug is identical, or bioequivalent to a brand name drug in dosage form, safety, strength, route of administration, quality, performance characteristics and intended use.  Although generic drugs are chemically identical to their branded counterparts, they are typically sold at substantial discounts from the branded price. According to the Congressional Budget Office, generic drugs save consumers an estimated $8 to $10 billion a year at retail pharmacies.  Even more billions are saved when hospitals use generics.

Are There Differences Between Generics and Brand-Name Drugs?

However, current regulations in the United States permit a variation of up to 20% either way in the bioavailability of the active ingredient. (See this Food and Drug Law Institute overview of the Hatch-Waxman Act of 1999.) Indeed, one study (Borgheini 2003) found a 31% variation in the blood plasma levels of a particular medication after a patient switched from a branded to a generic product. (Why would this happen? It may be accounted for by differences in the manufacturing process yielding different particle sizes that are absorbed at different rates, as well as other factors.)

Generics: Is the Savings Worth It?

This does NOT necessarily mean that purchasing generic medications in preference to branded counterparts is a bad idea -- in fact, in most cases it is probably still a very good idea! -- but this does mean that the issue is not quite as clear cut as it might otherwise seem.

When generics are available, they can offer tremendous cost savings. The only difficulty, of course, is that it sometimes takes many decades before pharmaceutical companies' patent protections run out and generics actually do become available!

Caution: When NOT to Switch Between Generics and Brand-Name Drugs

Treatment in the case of a few drugs is very sensitive to small variations in bioavailability. These are said to have a narrow therapeutic index, and patients normally should not change between generics and brand-name versions of these medications without close medical supervision. Such medications include (but are not limited to):

• carbamazepine
• divalproex sodium
• digoxin
• levothyroxine
• lithium
• phenytoin
• theophylline
• valproic acid
• warfarin

More Generic Drug Information

Abbreviated New Drug Application (ANDA) Process for Generic Drugs. Center for Drug Evaluation and Research (CDER).

http://www.fda.gov/cder/regulatory/applications/anda.htm

FDA Ensures Equivalence of Generic Drugs. FDA Consumer, special report, January 1995.

http://www.fda.gov/fdac/special/newdrug/generic.html

Trade-Name and Generic Drugs. Merck Manual Home Edition.

http://www.merck.com/mrkshared/mmanual_home2/sec02/ch017/ch017a.jsp

Generic drugs: saving money at the pharmacy. April 1998, Federal Trade Commission Web site.

http://www.ftc.gov/bcp/conline/pubs/health/generic.htm

Therapeutic Equivalence of Generic Drugs. Response to National Association of Boards of Pharmacy.

http://www.fda.gov/cder/news/ntiletter.htm