Epilepsy Talk

Anti-Epilepsy Drugs Lose Effectiveness Over Time… | October 10, 2017

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 (http://www.ilae-epilepsy.org/) 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. Okay we know all AED’s will lose their their power to stop or control all seizures & seizure activity over time to a 2, 3, 4 or 5 to 1 ratio, that we’re yo take more of,, depending what type of seizures that person is living with & how often seizures happen. When 500MGS has to be taken for what 100mgs use to work at doing, you know the drug makers are not making these drugs good enough to STOP all seizures & seizure activity because of all the chemicals, metals, additives, & preservatives in these drugs. If drug companies made all drugs in their purest forms, like compounded pharmacies can do, & keep the prices lower than manufactured drugs, then maybe we ALL could have good AED’s to take 365 days a year, to where only 1 drug is needed to take instead of 4 or more in most cases. Still there is NO AED, that will stop the man made MSG’s & ASPARTAME’s in the drugs, drinks & foods we have daily, yet as always that gets ignored when people like myself mentions that. Who has our backs & take a STAND FOR US ?


    Comment by C D — October 10, 2017 @ 10:21 AM

  2. Pretty much of a bummer…..One of my AEDs has been really good for me in terms of lack of side effects and I would really hate to have to stop it and switch to something else. The Zonisamide (generic form) I’ve been taking for several years, has never knocked me on my fanny (I’m talking to YOU Dilantin and Lamictal!)….just kept things even keel…..for a time anyway but, true to what you say Phylis, the neuro has had to up the dosage and, more recently add an additional AED on top of it….. (sad face)

    Liked by 1 person

    Comment by Ellen LaFrancis — October 10, 2017 @ 10:40 AM

  3. Several surgical anesthesiologists have told me over the years that people who take barbiturate based drugs for prolonged stretches acquire a tolerance for all barbiturates. These people (like me with my Phenobarbitol for decades) are harder to put to sleep for surgery and harder to keep asleep. One said, “your body just soaks up the anesthetic”. So, I don’t think this phenomenon is something entirely new to the medical community. It is interesting to see it getting more recognition outside of the anesthesia docs.

    I think you have a very valid point that a lot of people meat be way overmedicated.


    Comment by paleobird — October 10, 2017 @ 11:20 AM

    • Unfortunate but true. If it’s not working, just pile on another med, instead of blood work and homework. 😦


      Comment by Phylis Feiner Johnson — October 10, 2017 @ 2:18 PM

  4. “may” not “meat”. Darn you Autocorrect.


    Comment by paleobird — October 10, 2017 @ 11:23 AM

  5. I have posted before but my son, who is 13 now has tried over 6 medications in 8 years with very little seizure free effect, he now taking supplemental GABA the neurotransmitter found in the brain (and that most epileptics have a deficiency off) and that most of the drugs work to inhibit the uptake off, he has been seizure free (grand mals) for over 3 months and we have had none of the horrid side effects of all the drugs, I cant emphasize enough please do your research ask an integrative doctor its well worth it and your body will thank you for it, good luck xx


    Comment by jules lough — October 10, 2017 @ 6:54 PM

    • C.D., one of our members has written extensively about GABA and it’s importance.

      I can see your wisdom and wish that others followed your example.


      Comment by Phylis Feiner Johnson — October 10, 2017 @ 7:23 PM

  6. you can get hooked on pain killers because you get used to them and start taking more and more, I’ve often wondered had the same happened to my AEDs as my condition sometimes changed, and that bit about weight gain really is important as so many of them, like Epilim cause weight gain


    Comment by Gail — October 11, 2017 @ 2:06 AM

    • Good question.

      I don’t think you can get hooked on AEDs, but as reported, they can lose effectiveness. Not the same as being “addicted” to pain killers.


      Comment by Phylis Feiner Johnson — October 11, 2017 @ 9:08 AM

  7. Reblogged this on catsissie.


    Comment by catsissie — October 11, 2017 @ 3:46 AM

  8. Thanks for the information. Are there certain AEDs associated with the problem or is it universal? It happened to me with dilantin after 34 years.


    Comment by Tom Waltz — October 11, 2017 @ 7:00 AM

    • I think it’s pretty universal.

      But you’re right, it does depend upon upon the med, your metabolism and your tolerance for the med.

      That’s why it’s good to have blood work done from time to time. To see if the levels of drugs in your system are at their proper levels.


      Comment by Phylis Feiner Johnson — October 11, 2017 @ 9:12 AM

  9. I am so glad that todays standards are after 2 or 3 drugs fail to control a patients seizures surgery or device implants are brought up for treatment options.

    I have been on a dozen (yes 12) seizure medications over the years starting 1981. The last 18 years or so three drugs was “normal” for my attempted seizure control until the surgery.

    Having been maxed out on several drugs over the years makes you very aware of risks and side effects. For me that was: 2200mg/day of Tegretol. 5000/day of Keppra. 2400/day of trileptal (all of those taken along with other drugs). Increasing the dose to extreme levels doesn’t mean you will gain control. Often side effects outweigh the positive side of medications.


    Comment by Travis — October 14, 2017 @ 11:10 AM

  10. Please see msg I left in the section on epilepsy medication and ostioperosis thanks ..


    Comment by Valerie Wells — October 30, 2017 @ 2:16 PM

  11. I have had 2 temporal lobe surgeries for partial focal-absence seizures. They hav’nt worked and I’m still having seizures. Dr. has added a med to what I already take. Dr. said it was a newer med and it should take care of my seizures. I hope it works because my last seizure was one of my worst seizures.


    Comment by Monica Ponce — November 9, 2017 @ 1:34 PM

    • What med is it. Have you researched it?


      Comment by Phylis Feiner Johnson — November 9, 2017 @ 1:36 PM

      • this is my situation exactly, been dealing with ignorance in my immediate family, most friends and doctors not really understanding my very different situation , doctors are trained to believe they are smarter than everyone. but in my situation being a scientist, a researcher and an chemical engineer they dismiss me and have trouble acknowledging someone can know more about his own problem that any doctor might know, even the recommendation for surgery by my doctor did nothing but make a lot of money for the medical world without helping me one bit. and left me with half of a brain. and a lot of people still convince they and the doctors are right and I know very little of my situation at age 68 i have more drive, energy work experience and education than people in their 30’s and 40’s, and likely always will


        Comment by James Colaianne — December 25, 2017 @ 1:52 PM

      • Bravo for you James. You’re a survivor. (Literally.)

        Don’t stop fighting and don’t stop believing in what you feel and know about yourself.


        Comment by Phylis Feiner Johnson — December 25, 2017 @ 5:31 PM

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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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