More Side Effects… Less Effective?

Generic drugs cost 30% to 80% less than their brand-name counterparts and most people feel safe taking them because the FDA requires that both types of medications provide the same active ingredients and level of effectiveness.

Recent development: A 2006 survey found that about 25% of 300 doctors throughout the US don’t believe that generics are chemically identical to brand-name drugs… nearly one in five believe that generics are less safe… and more than one in four believe that generics cause more side effects.

So what’s the truth about generic drugs?

WHAT PATIENTS SAY

Since 1976, when our book The People’s Pharmacy was originally published as a consumer guide to drug and health information, thousands of patients have contacted us about their experiences with medications.

In the last few years, we’ve received hundreds of letters and E-mails — most of them complaints — about generic drugs, including pain relievers, antidepressants and blood pressure medicines. The number of such complaints has increased dramatically in that time.

What we’ve learned: Some patients who switch from a brand-name to a generic drug report a decline in effectiveness — for example, blood pressure that isn’t controlled as well or a worsening of depression. Others report having a rash or other types of allergic reactions, probably due to one of the inactive “filler” ingredients in generic drugs. There also seem to be problems with the timed-release mechanism of some generics.

Example: We’ve heard more than 100 complaints about a generic version of the long-acting anti-depressant Wellbutrin XL. At least one manufacturer’s timed-release generic formulation appears to be different from the brand name — and may be releasing too much of the drug too quickly (known as “dose dumping”). This would explain many of the side effects, such as headaches and anxiety, that some people tell us they experience when they take the generic drug, but not the brand-name version.

We’ve contacted the FDA about the complaints regarding this generic drug, and we’re also working with an independent laboratory to analyze this formulation.

IS THE FDA DOING ENOUGH?

Drug companies must apply to the FDA to sell generic versions of drugs. To gain FDA approval, a generic drug must contain the same active ingredients as brand-name medications and meet the same criteria for such factors as quality, strength and purity. Possible problems with generic drugs…

  • Periodic checks for impurities. The FDA monitors generic drugs, testing for such things as proper dosing and active ingredients. But the agency only checks about 300 “dosage forms,” such as tablets and capsules, among brand-name and generic products a year — out of a total of more than three billion prescriptions.
  • Infrequent inspections. The FDA is supposed to inspect each US drug manufacturing plant every two years — but lacks the resources to meet that requirement.
  • Overseas manufacturing. An enormous percentage of drug ingredients and raw materials for drugs (primarily generic and over-the-counter) come from India, China and other countries where quality assurance is not as rigorous as in the US — and where drug counterfeiting has been a problem.

    • Trap: Overseas plants are inspected much less frequently than those in the US. Without testing, there’s no way to tell whether drugs and drug ingredients derived from these plants have impurities — or come in “subtherapeutic” doses (for example, a drug labeled as 10 mg may be only 6 mg).

    STAYING SAFE

    Most of the evidence for problems with generic drugs is based on anecdotal reports. However, research published in Neurology in 2004 reported that people with epilepsy who switched from the brand-name form of the antiseizure drug phenytoin (Dilantin) to the generic form of the drug began to have higher-than-expected rates of seizures. Investigators found that in many patients, blood levels of the active ingredient had dropped by 30%. Even so, patients should not give up on generic drugs. The cost savings can be considerable… and there’s no evidence so far that the majority of generic drugs will cause problems for most patients. Patients using generic drugs should simply take extra precautions…

  • Stick with one manufacturer. This is particularly important if you’re taking a drug with a narrow therapeutic index (NTI), such as the anticoagulant warfarin, the antipsychotic lithium or the anticonvulsant carbamazepine. NTI drugs, which typically require periodic blood tests to measure blood levels of the medications, have a very thin margin between an effective dose and a toxic dose. If you’re taking a generic form, ask your pharmacist for the name of the manufacturer — and request that the pharmacy stick with that company, if possible, to avoid variations between products.
  • Track your numbers. Many conditions, such as hypertension or high cholesterol, don’t cause obvious symptoms. The best way to tell whether a drug is working is to monitor your numbers — by taking daily blood pressure readings, tracking blood-sugar levels and keeping track of cholesterol levels with frequent blood tests at your doctor’s office.

    • Important: Ask your doctor to give you copies of your test results. Check them periodically to make sure that you’re maintaining adequate control — particularly if you’ve recently switched from a brand name to a generic, or the reverse.

  • Trust your instincts. Some medications affect the body in subtle ways. A patient taking a thyroid drug, for example, might feel slightly run-down if it isn’t working exactly the way it should, even if test results appear to be normal. Pay attention. If you’ve switched to a generic and notice a difference — either in effectiveness or side effects — tell your doctor.
  • Do a “challenge, rechallenge” test. If you suspect that a generic drug isn’t working the way it should, write down changes in how long the drug works and side effects. Then, ask your doctor to switch you to the brand-name equivalent, and see if there’s improvement — in most cases, it will be apparent in about two weeks. Under the close supervision of your doctor, repeat the test, going back and forth until you have a clear idea which drug is more effective for you.
  • Report problems to the FDA.* The FDA can analyze generic drugs to determine if they contain the stated amount of active ingredient. When reporting a drug to the FDA, ask your pharmacist to provide the name of the manufacturer, the lot number and exactly when the drug was dispensed to you.

    • If you’d also like to report problems with generic drugs to us, go to The People’s Pharmacy Web site, www.peoplespharmacy.org.

    *Go to the FDA Web site, www.fda.gov/medwatch, or call 888-463-6332.