Healthcare News & Insights

Generics may not be as effective as we thought

The more research that’s done, the more some physicians worry that generic meds do work differently than the brand names they copy.

No one is suggesting that generics don’t have a place in the health care system. But especially when it comes to cardiology and neurology, doctors are becoming more skeptical that generics can automatically be assumed to be a perfect equivalent for name brand drugs — or even other generics for the same drug.

Blood levels and bioequivalence

While all generics must have the same active ingredients at the same strength, they are only required to provide very close blood levels. Some practitioners think slight variations in how dosages metabolize could cause side effects or other difficulties — particularly in cardiology and neurology where patients tend to be sensitive to even very slight changes in dosages.

To test the theory, one consumer group ran tests on Wellbutrin XL and its generic version, Budeprion XL 300. According to the tests, the two drugs did have different diffusion rates for the active ingredient, which could cause decreased effectiveness of the generic in some patients who switched to it from the brand name.

At particular risk of side effects or complications are patients who start taking one brand name or generic drug, and then switch to another. That’s especially true since patients on generics may not be informed when their pharmacist substitutes one generic for another.

Regardless, the FDA and the AMA both stand by generic medications and say the varying diffusion rates are still well within the standards set to maintain effectiveness of the drugs.

One thing is clear: More research is needed to figure out exactly how varying diffusion rates could effect a patient’s treatment. In the meantime, it’s probably worth it to explain to patients that while generics work and are safe, they shouldn’t ignore it if they do start to have side effects when switching prescriptions (or even after starting a new refill.)

If you’ve had experiences with patients having bad reactions to generics, share them in the comments.

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  1. Sounds like a big chunk of propaganda to me. Sounds like saying a generically measured two feet wont be as long as two feet measured by a contractor.

    Seems that they trademark those drugs so they can make their money. They make generics if the drug has been around long enough to warrant it. I wont trust any drug that does not have a generic counterpart. Simply because then you really have no idea how well it works in the general population.

  2. Also Anon says:

    I don’t think it’s all propoganda. Having taken “brand name” and generics for allergies, my experience is that the generics do not work as effectively or as consistently as the brand name medications.

  3. I think there is some truth to this. The “brand name” and generic for thyroid problems caused a definite change in me. I and numerous others I have spoken about this, can only take the brand name. I also saw a change in my Mother on her heart medicine when she took the generic instead of the brand name. I am sure some generics are just as effective, but some are not as determined by own personal experience.

  4. “Two feet” doesn’t contain chemicals that you then put in your body! SOME generics are okay, but patients have to be aware that they AREN’T the same. Try placing a brand name drug in a glass of water, and a generic equivalent in another glass. Usually the brand name will dissolve better. Which means they’ll also get into your system better. Patient that have had problems KNOW to request no generics.

  5. maybe the rating system for generic products needs to be re-evaluated.

  6. Your right. Two feet does not contain chemicals, two feet contains distance. A tape measure measures distance, the FDA regulates drugs. FDA and the AMA say the generic is the exact same chemical makeup, composition, etc are the same.

    Also, they never said anything about the drugs being less effective, or even different, just that their diffusion rates were different.

    Maybe one should consider a generic one a day rather than an extended release capsule?

  7. Ask people with cardiac arrythmias who went from using brand-name amiodarone to the generic. Or rather maybe ask their attending cardiologist for their opinion.

  8. I would liken comparing a generic drug to a brand name drug as similar saying a Yugo is just as good as a Mercedes because they are both automobiles. Sure, they will both get you from A to B in roughly the same time, but what about the subtler aspects such as performance and reliability. You get what you pay for, in cars or in medication. There is a great deal of expense an risk in the process of developing a new medication, and we all are aware of the benefits to patient’s quality of life. The reward for this is a decent profit margin that encourages investment in the company, happy employees, and capital to reinvest in development of even better drug therapies.
    My own personal experience in treating an autoimmune arthritis condition tells me different versions of the generic medication have different levels of effectiveness, which is absolutely no surprise to me. They both work, but one provides more relief than the other. Hence, they are not “equally effective”.