Epilepsy Talk

Dilantin — Hero or Horror?  | November 14, 2021

Dilantin (Phenytoin) can be considered the grandfather of all epilepsy medications.

Although it was invented in 1908 as a chemical that could prevent convulsions during electroshock treatment, its popularity grew quickly, and as early as 1940, it was hailed as initiating a whole new epoch of anti-epilepsy drugs, motivating researchers to seek even more effective medications and pharmaceutical companies set up aggressive screening programs.

In the next two decades, a dozen new anticonvulsants were introduced into clinical therapy!

Today, Dilantin remains one of the most widely used drugs in the world.

Although in most cases, it is now a second-line therapy, it’s still the drug of choice in the emergency treatment of seizures and status epilepticus.

But for the most part, Dilantin has been used for treating generalized and partial tonic clonic seizures and complex partial (psychomotor, temporal lobe) seizures.

It’s also used for prevention and treatment of seizures occurring during or following neurosurgery.

It may be used alone as mono therapy or with phenobarbital and  other AEDs.

Since it first came out, Dilantin has always had its fans and its detractors.

Who can forget Jack Nicholson’s out-of-control behavior as the “crazy?” in Ken Kesey’s “One Flew Over the Cuckoo’s Nest”!

But some committed themselves to championing Dilantin for anxiety control and mood stabilization…

Dilantin as an anti-depressant…

The famous Jack Dreyfus, founder and former head of the Dreyfus Fund, left Wall Street in the 1960s and started the Dreyfus Health Foundation to research and promote the drug, which he credited with having turned around his depression.

Dreyfus believed that Dilantin was a wonder drug that could promote positive mental health by controlling anger and depression.

And he contributed more than $70 million in personal financing to see Dilantin approved for those alternate uses.

Dreyfus also claimed to have supplied the drug to the late President Richard Nixon to rectify Nixon’s poor moods both during and after his presidency.

Nixon’s former aides denied the story, but Dreyfus stuck to it and even expanded on it during an interview in 2000.

”When he was 70 he was here and he asked for more, and I gave it to him,” Dreyfus told the New York Times.

Dreyfus detailed his passions and his views of the drug in his book “A Remarkable Medicine Has Been Overlooked.”

But despite financing four decades of research into the anti-depressant benefits of Dilantin, Dreyfus failed to sway the FDA.

He died in March 2009.

Ironically, just a year before Dreyfus’ death, Dilantin was put on the FDA’s Potential Signals of Serious Risks List to be further evaluated for approval.

The list means that the FDA has identified a potential safety issue, (one was quality control), but it does not mean the FDA has identified a causal relationship between the drug and the listed risks.

Possible risks…

There are some dangers of Dilantin, here are a few…

Bone Weakening — Long-term use of Dilantin is associated with decreasing bone density, making bones more fragile which can eventually result in fractures.  So osteoporosis is a major concern. However, this is more likely if the drug is combined with other anti-seizure medications. Patients can decrease this risk by taking Vitamin D supplements, eating calcium-rich foods and exercising regularly.

Gingivitis — Up to 40 percent of patients using Dilantin long-term, experience an overgrowth of their gums, which is more common in children than adults. This can be minimized by vigorous brushing, daily flossing and treatments by dentists.  (But I’ve had galloping gum rot for 40 years!)

Neuropathy — People taking Dilantin for many years also can develop sensory peripheral polyneuropathy, or nerve damage, which can cause pain, tingling or numbness in the feet and legs.

Stevens-Johnson Syndrome – This is a rare, serious disorder in which your skin and mucous membranes react severely to a medication or infection. Often, Stevens-Johnson Syndrome begins with flu-like symptoms, followed by a painful red or purplish rash that spreads and blisters, eventually causing the top layer of your skin to die and shed. It’s considered a grave medical emergency and can be life-threatening.

Purple Glove Syndrome – The FDA is investigating whether Dilantin causes Purple Glove Syndrome, a skin disease that causes swelling, discoloration and pain in the arms and legs. In serious cases, it can force amputation of affected limbs.

Birth Defects – If taken during pregnancy, Dilantin and barbiturates can cause cleft lip or palate, or other skull, face or heart malformations.

Brain Atrophy — Long-term Dilantin use is also associated with atrophy to the brain cerebellum, but it is rare for people to experience significant problems related to this side effect.

Side effects…

Interestingly, Dilantin is the most prescribed AED by general physicians in the U.S. but less so among epilepsy doctors, because of its side effects.

That says something in itself!

If you have diabetes, this drug may increase your blood sugar levels.

Check your blood (or urine) glucose level frequently, as directed by your doctor.

Promptly report any abnormal results as directed. Your medicine, exercise plan, or diet may need to be adjusted.

Dilantin can cause anemia by reducing folic acid in the body, a particular concern for women considering pregnancy.

Unusual eye movements, slurred speech, loss of balance or coordination, confusion, hallucinations can occur.

Along with mood or behavior changes, depression, anxiety, agitation, hostility, restlessness, hyperactivity (mentally or physically), unusual behavior or thoughts about suicide or hurting yourself which can happen with Dilantin. (So much for Jack Dreyfus!)

Other possibilities are: tremor (uncontrolled shaking), restless muscle movements in your eyes, tongue, jaw, or neck, double or blurred vision, tingling of the hands/feet, facial changes (e.g., swollen lips, butterfly-shaped rash around the nose/cheeks).

More side effects include bone or joint pain, swollen glands, easy bruising or bleeding, swollen or tender gums.

Also headaches, sore throat, fever, nausea, vomiting, constipation, dizziness, unusual tiredness and conversely, insomnia are included.

And if you’re real thirsty or constipated, don’t be surprised.  Unfortunately, that seems to be the price of all AEDs.

Try Xylitol, a natural sugar substitute that helps with the dry mouth that many of us suffer.

And Salba, a natural fiber that’s a rich source of Omega-3 fatty acids and is also a natural laxative.  (Believe me, it works!)

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  1. Aside from all the possible side effects, Dilantin has worked for me (since 1973). But it was a rough road to understanding how it works in my body. It metabolizes slowly and I had to learn how to manage my doses. Most recently, I retired. So what’s wrong with that? Medicare doesn’t cover Dilantin ($545 for 90 day supply), but Medicare (and my advantage plan) will cover its generic cousin, phenytoin. Problem is that my doctors have advised me not to change from Dilantin to the generic version ($26 for 90 day supply). Has anyone heard of the risks of swapping Dilantin with phenytoin? If you know of any research please reference that. Thanks.

    Liked by 1 person

    Comment by TOM WALTZ — November 14, 2021 @ 12:44 PM

    • Tom, Your doctor knows more about your seizures & medications deeply in detail than Medicare.
      Therefore, your doctor should be the only professional medical expert who should prescribe your medications for your pharmacy to provide & Medicare to follow through the Doctor’s prescription.
      Medicare should NOT be in business of swapping medications without your Doctor’s approval.
      Therefore, ask your Doctor to write a letter to Medicare insisting that Medicare should NOT replace your medications from Dilantin into Phenytoin.
      I had been in your shoes, until my Doctor intervened with the Medicare bureaucrat oligarchy.
      Our medical hardships should NOT get traded for the cheapest bidder.

      Liked by 1 person

      Comment by Gerrie — November 14, 2021 @ 10:24 PM

  2. “The issue with phenytoin is it is the single most difficult anticonvulsant drug to use because it has very different metabolism than most medicines,” Barkley tells WebMD. “Small changes in dose result in wild swings in metabolism.”

    The small differences between Dilantin and generic phenytoin can have big clinical effects.

    “Given the nature of the thin margin between too much and too little phenytoin, I am not surprised switching from one brand to the other makes problems,” Barkley says. https://www.webmd.com/epilepsy/news/20041025/generic-epilepsy-drugs-not-same

    People who switch from brand-name Dilantin to generic phenytoin possibly risk having more seizures or side effects during the changeover, because the body does not absorb the different types in the same way. Switching from one company’s generic phenytoin to another company’s may have similar risks. So can switching from generic phenytoin to Dilantin.

    All these risks are not fully known. For some people the effects of changing from one type to another are very small. Some use generic phenytoin successfully by always using the same company’s product. Then the dosage can be adjusted to achieve the best results. https://www.epilepsy.com/medications/phenytoin

    Tom, I hope this helps.


    Comment by Phylis Feiner Johnson — November 14, 2021 @ 12:56 PM

    • I had a hell of a time getting my Dilantin regulated in the beginning. I was toxic for some time before I realized what was happening. Tri I tried to come off Dilantin and switch to something else but ended up going back into status as I was weaned off of it and then had add Keppra and lamotrogine to get my seizures back under control. Fooling around with meds and finding the right cocktail is no fun. The side effects of being on three are not easy, maybe if I had stuck with Dilantin to begin with that would have been enough…lol

      Liked by 1 person

      Comment by Dennis j Crocker — November 14, 2021 @ 2:34 PM

      • I also went toxic on Dilantin. Got galloping gum rot and my beautiful hair fell out. But in those days, there was only Dilantin or Pheno (goes to show you how old I am). So it was the devil you know versus the devil you don’t know. I was stuck.


        Comment by Phylis Feiner Johnson — November 14, 2021 @ 4:00 PM

  3. Dilantin was the last of three drugs I went off of after surgery. I know it had side-effects. I watched my gums swell and I also saw them get back to normal when I stopped taking it. I’ve lost half of my teeth. It lowered my Vitamin D level to a dangerous level when I finally decided to let go.

    I was on Dilantin for 35 years because no matter how many side-effects it had, it was helping control my seizures.

    Liked by 1 person

    Comment by Ed Lugge — November 14, 2021 @ 2:43 PM

  4. Tom, I have Medicare advantage and I got my physician to write a note saying that I must have Dilantin not generic phenytoin. There are plenty of peer reviewed publications that support the fact that some people who have been on Dilantin for years may react badly to changing to generic phenytoin. A simple google search is all you need.

    Dilantin is a wonder drug (with potentially horrible side effects) for those of us who respond well to it. Achieving the right dose is difficult because only 100 mg and 30 mg capsules are available. For me 400 mg daily became problematic (blood level too high) after decades of using it. My Physician suggested decreasing to 300 mg daily but it proved to be too low a dose so I chose to take 300 mg for two days and 400 mg on the third day which surprisingly actually works well for me. I am not recommending that anyone else do this without involving their physician because clearly there are risks in changing drug doses. Also, there is not a straight linear relatioship between dose level and blood level with Dilantin so one needs to lower dosage levels incrementally in stages.

    Liked by 1 person

    Comment by Michael H — November 14, 2021 @ 6:13 PM

    • Thanks Michael. What Medicare advantage plan do you have? I’d like to know if it’s available in my area. Yes, as of Monday this week, I have one of those “must have brand name Rx” letters ready to go.

      Sounds like you’re exactly like me…the 400 mg/day was always too much for my metabolism. I was the poster child for the walking dead nearly every morning for 25 years. My current pcp and I figured it out together (20+ years ago). So I do the same as you…alternate 300 and 400 mg/day.

      Anyway, I am researching Medicare advantage plans to find one that will cover Dilantin at a higher rate than Regence. Even with the “must have” letter from my doc, Regence will only pay $140 for a 90 day supply, leaving me with a $340 copay. There must be an alternative to Regence.


      Liked by 1 person

      Comment by Tom — November 18, 2021 @ 8:08 AM

  5. Having tried Lamictal, Keppra, Dilantin, Phenytoin,,, at different stages of my epilepsy in the last 20 years, I was more concerned with controlling my seizures than with the side effects of my prescriptions.
    And never having deep understanding of the side effects of my medications, I always attributed the physical & mental changes I had been going through the last 20 years to aging.
    Little did I knew there has been much more going on to my physical & mental changes than just aging.
    Thanks for your informative brilliant article detailing the benefits & listing the side effects of Dilantin, the medication I had been taking for many years, now I know there’s more going on to my physical & mental conditions than just aging.

    Liked by 1 person

    Comment by Gerrie — November 14, 2021 @ 11:02 PM

  6. I’ve taken Dilantin for years & I feel
    it’s done wonders for me.
    I’m Epileptic & have tried several
    different drugs for my Epilepsy.

    Liked by 1 person

    Comment by Robert Christian — November 15, 2021 @ 10:02 AM

  7. My son has been on Dilantin (Name brand only) for 4 years with very good seizure control. He takes 200 mg in the am and 300 mg at night, both are the slow acting where it releases a certain amount over time. He also takes Vit D and Magnesium at night. He has had 2-3 break through seizures caused by stress in college or too much caffeine. Once he drank an energy drink which is a big no no with E.
    He just now started showing signs of gum overgrowth and he is working with his dentist to combat that side affect.
    We praise God that this med works well for him.
    He is 21 and will graduates college in May.
    He has had E since he was 7.
    Prayers for a great last semester would be appreciated.

    Liked by 1 person

    Comment by Tami — November 15, 2021 @ 1:54 PM

  8. Tami, we’re praying, but it looks like you’ve got things well under control. Just keep him away from those energy drinks. They’re poison.

    Epilepsy and Energy Drinks — Think Before You Drink! https://epilepsytalk.com/2021/06/07/epilepsy-and-energy-drinks-think-before-you-drink/

    And you might want to add a Vitamin B Complex to his vitamin regimen.

    Without a question, they are the star of all vitamins. In sufficient quantities, especially those that combine B6, B12, folic acid, thiamine and biotin, they are vital to the production of numerous brain chemicals.

    Like the neurotransmitters which serve as the chemical message bearers between your nervous system and brain.

    The most efficient way to make use of this “brain food,” is to take it in a B complex form, since this contains all the vitamins in the B group. And when combined, they work synergistically together.

    Take a single B-50 B complex tablet twice a day with food.

    Each dose should contain 50 micrograms of vitamin B12 and biotin, 400 micrograms of folic acid, and 50 milligrams each of all the other B vitamins.


    Comment by Phylis Feiner Johnson — November 15, 2021 @ 2:03 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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