Epilepsy Talk

Anti-epilepsy drugs lose effectiveness over time… | March 7, 2023

It may be the dose prescribed…the type of epilepsy you have…even something as simple as your age or weight.

But research shows that, over time, the effectiveness of your anti-epilepsy drug may decline.

Almost all first, second and third-generation epilepsy drugs lose their efficacy after prolonged treatment.

Perhaps it’s because your metabolism builds up a tolerance to the drug. And ramping up the dosage can work.

Or it may be a functional tolerance where your brain receptors have become resistant to the drug. In that case, a change in medications may help. But whatever the cause, you’re not alone…

Patients showing tolerance to traditional drugs:

A critical review by Dr. Wolfgang Loscher and Dr. Dieter Schmidt shows that repeated administration of anti-epileptic drug (AED) therapy has diminishing results in preventing seizures in epileptic patients.

In clinical trials, the number of patients remaining seizure-free declines over time with prolonged treatment.

This review explores how acquired tolerance, the adaptive response of the body to foreign substances, as opposed to innate tolerance (which occurs in patients naturally resistant to certain medications) is responsible for this diminishing effect.

The risk of developing a tolerance to AEDs was traditionally thought to be small.

Loscher and Schmidt, however, conclude that while AED tolerance is not a serious issue for most sufferers of epilepsy, it is a significant aspect of treatment in some patients.

A few may even develop a cross-tolerance to similar medication. This “multi-drug resistance” is of serious concern to patients with medically intractable epilepsy.

The findings directly conflict with the treatment method many doctors are currently using…

It is standard practice to increase AED dosage until adequate seizure control is obtained. However, this protocol presents a number of issues.

The threat of medication tolerance is generally overlooked, as is the idea that epilepsy can be a progressive disease and does not develop at a fixed rate.

Further, patients may acquire a tolerance to some effects of a particular drug, but not all.

Loscher and Schmidt have spent decades studying the effects of AEDs, however, Loscher believes that AED tolerance is a topic that has yet to be fully explored, and that more long-term clinical trials are becoming increasingly necessary.

“Despite the convincing experimental evidence,” says Loscher, “tolerance to the effectiveness of AEDs seems to have been forgotten.”

Research is currently being done on the effects of placebo and conditional tolerance (a mental, conditioned-response effect that the mind has over the body).

Doctors are also studying the effects of lower initial and target doses of AEDs.

The possibility exists that many patients are being over-medicated from the start, posing a significant challenge to doctors and scientists working toward effective seizure control.

This study was published in Epilepsia magazine.  Epilepsia is published on behalf of The International League Against Epilepsy the world’s preeminent association of physicians and other health professionals working towards a world where no person’s life is limited by Epilepsy. Its mission is to provide the highest quality of care and well-being for those afflicted with the condition and other related seizure disorders.

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  1. This was something that I really didn’t need to be reminded of after 61 years of having some drugs work good only for a while, yet I knew as a kid, & teenager that the neurologists I saw back then in the 1960’s & 70’s did not care how much they were giving me to take, knowing all I was taking were good downer barbituates. Since taking XCOPRI with VIMPAT for 16 months, it’s been a seizure free ride & I have to be on notice that drugs one day will suddenly STOP working? The past has told & showed me that, as today what I am on are not barbituates but CS’s Controlled Substance drugs, and I still am not eating & drinking anything much in the P&G processed foods, loaded with MORE & MORE NITRATES, NITRITES, < KILLER BRAIN CELL TOXINS THEY ARE, MGS's,/MONOSODIUMGLUTAMATE, ASPARTAME's, CONCENTRATES, ISOLATES, POWDERS, EXTRACTS, FLAVORS, & alike. I always have said, that all people with a BRAIN CHEMISTRY, if it never gets emptied of these toxins, like emptying a RAIN GAUGE when it never gets emptied, well the rain overflows as will toxic chemicals & poisons in all brain chemistry that can never eliminate the body, since they never get DETOXED & EMPTIED, so more seizures WILL happen, until you starve your brain from those things. SINCE AT LEAST 1988, I have examined my own brain chemistry by the BRAIN TALK it tells me as I know THE BRAIN NEVER LIES to you, when you know HOW to listen to it OR other people who may know a little bit about these AED's, foods, drinks & alike, as GENERIC name AED's never will match to BRAND NAME AED's to take. Processed drinks & foods are GENERIC & gambling with your brain chemistry, as is taking GENERIC drugs or any OTC drugs alike, that CAN make your AED's not work as good as they could or should.

    Liked by 1 person

    Comment by James D — March 7, 2023 @ 4:42 PM

  2. I got hooked on codein, the only drug that seemed to work on my headache, but it failed over a few weeks I overdosed had bad side effects, it stopped working and it took me a long time to ditch them, my epilepsy drugs I’ve always been suspicious of as my neuros have kept me on them too long, sometimes increasing the dose until I was taking too much , sodium valproate even became toxic I’ve been on lamotragine for years and trying a second drug with it, which never works, I’d love to get off that ancient drug

    Liked by 1 person

    Comment by Gail Barry — March 8, 2023 @ 10:30 AM

  3. Codeine almost killed me. Yet Lamotragine and Klonopin have been my saviors.

    Different strokes for different folks. I hope you soon find you magical medicine mix!


    Comment by Phylis Feiner Johnson — March 8, 2023 @ 10:36 AM

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    About the author

    Phylis Feiner Johnson

    Phylis Feiner Johnson

    I've been a professional copywriter for over 35 years. I also had epilepsy for decades. My mission is advocacy; to increase education, awareness and funding for epilepsy research. Together, we can make a huge difference. If not changing the world, at least helping each other, with wisdom, compassion and sharing.

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