Warning: Generic Drugs Not Always Equivalent to Name Brands

September 18, 2008

generic drugs2Beware the potential dangers of switching from a brand name to a generic drug.  Lynn Nelson, of Tampa, learned that lesson the hard way three years ago.

 “I switched from Synthroid to a generic and my thyroid went berserk,” said Nelson.  She’s had hypo-thyroid condition for 25 years and had been taking Synthroid for all those years with no problems.  When the generic version, levothyroxine sodium, came out about three years ago, her doctor switched her prescription. 

 “My hair started to fall out. I was exhausted all the time. I had body aches.  I felt like I had the flu.”  Nelson didn’t understand what was happening, so she jumped on the internet to do some research.  Much to her shock she discovered the generic version of Synthroid had been recalled, but her doctor was never notified.  

“I was angry,” Nelson says.  “I didn’t want to take the generic to begin with, because I never thought it was the equivalent.” 

The vast majority of generic drugs are safe and a less expensive alternative to brand named drugs.  However, generic drugs are NOT the exact duplicate of the brand name and not all generic drugs are manufactured to the same exact standards of brand named drugs.


 Last month, the Federal Drug Administration (FDA) forced a recall of 65 different generic drugs manufactured by Actavis Totowa LLC.  Actavis is one of the largest generic drug manufacturers in the United States.  Regulators found that the company’s Little Falls, N.J. plant didn’t meet minimal safety standards for pills.  Some of the pills that were recalled were potentially very dangerous such as Oxycodone. Click here for a full list of drugs in question.

This week, the FDA announced that it will block imports of generic drugs manufactured by Ranbaxy Laboratories Ltd, a major manufacturer from India.  The recall covers 30 generic medications such as Cipro, Alavert, and Claritin. Click here for a full list of the drugs in question.

The FDA has been woefully understaffed for years.  The stress ridden agency has struggled to keep its head above water to deal with safety problems.  Last week the FDA increased its staff by 10%, but this only brings the agency back to where it was years ago. Without proper staffing safety problems are bound to continue to plague the FDA.

Requirements for Generics

To gain FDA approval, a generic drug, among other things, must contain the same active ingredients as the brand name, but NOT the same inactive ingredients.  The generic must also be the bioequivalent of the brand name, but NOT the exact equivalent.  For a drug to be the bioequivalent, it is supposed to deliver the same amount of the active ingredients in the same time as the original. This presents two serious health issues.

Problems with Generic Drugs

The first and most common problem is that the inactive ingredients are different.  The inactive ingredients can affect how quickly the active ingredient is absorbed from your stomach to your body which in turn may affect how much medication you get.  Also, some people may be allergic to the fillers and dyes used in the generic substitute.

The second and more serious problem involves drugs with a Narrow Therapeutic Range or Index such as Synthroid, the drug Lynn Nelson takes.  Synthroid is used to regulate the thyroid.  Very small changes in absorption rates can cause the drug to be ineffective, as in Nelson’s case.

“When the doctor tested me three weeks after taking the generic, it was like I was not taking a drug at all,” Nelson explained.

Even though the generic form, levothyroxine sodium, may be the bioequivalent of the brand name, Synthroid, it is not the exact same drug, and while the absorption rate for the generic may be within FDA tolerances, it is not exactly the same.

The American Thyroid Association (ATA) has surveyed thyroid experts and found that doctors believe the current FDA standards for the generic alternatives to Synthroid may lead to negative health effects in some patients.

When Generics May Not Be Appropriate

There are certain conditions when generic substitutes may not be appropriate.  For example, hormones are usually taken in very small doses, so differences in brands could produce major swings in the response.  Cortico-steroid creams fall under this umbrella.  They are standardized by skin tests and although rated as bioequivalent, responses to the drug can vary for individuals. For a chart of other drug categories please go to the following link.


According to Dr. Stevens Gans, Psychiatry Instructor at Harvard Medical School, there are precautions you should take if a generic drug has been prescribed. 

First, trust your body.  If you feel bad, call your doctor. 

Second, note the manufacturer of your drug and check each time you re-fill your prescription to see if the manufacturer has changed.  If a medication has changed from brand name to generic, or from one manufacturer to another, you may want to start taking the new pills while you still have a few of the old ones left.  If you exhibit an allergic reaction or the new medication does not seem to have the same effect as the old one, switch back and see whether the allergic reaction disappears or the old medication works better.  It’s important to let your prescribing doctor know if you are experiencing any problems.  Obviously, if you have a severe reaction at any time to a medication, get help immediately.

After Lynn Nelson’s bad experience with the generic drug for her thyroid condition, she returned to taking the brand name Synthroid and her condition stabilized.  She says she now avoids generics like the plague.  “You can’t tell me a drug that cost $50 to produce today and only $5 tomorrow meets the same quality and standards.  I am not a fan.”

Reporter Angie Moreschi contributed to this story.