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Phenytoin and Drowsiness: What Users Say

Brand names: Dilantin, Phenytoin Sodium, Phenytoin Sodium, Extended Release, Phenytek, Di-Phen

Drowsiness: mentioned by 4 users (3.4%)

Based on user experiences from 116 Phenytoin reviews, the following table shows the most commonly mentioned side effects.

All user comments are moderated by Drugs.com. Each review is verified for relevance and screened for inappropriate content. Side effects are user-reported and not clinically verified.

dizziness 10.3%
rash 7.8%
memory loss 6.9%
swelling 6.9%
seizures 5.2%
fever 4.3%
drowsiness 3.4%
headaches 3.4%
nerve pain 3.4%
tiredness 3.4%

Reviews for Phenytoin

Showing 4 reviews tagged with "drowsiness". Clear filters to view all 116 reviews.
Commonly mentioned side effects
  • D P...
  • Taken for 10 years or more
  • February 23, 2015

Phenytoin for Seizures "I had my first ever seizure on 8/4/93, one day before my 24th birthday, out of the 'clear blue.' I was first prescribed 400 mg of Dilantin daily. I experienced muscle spasms/twitches, sleeplessness at night, and sleepiness during my waking hours. I was switched to 400 mg of Phenytek daily. At first, the same symptoms persisted but subsided over time. I have been on both Dilantin and Phenytek for 22 years; currently on Phenytek, and my seizures are controlled, with minor/minimal side effects: occasional muscle twitching and/or headaches remedied with Tylenol. I hold down a full-time job, and I drive, so my #1 priority every night is to take my meds. So far, so good....."

10 / 10
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10 Report
  • D P...
  • Taken for 10 years or more
  • February 23, 2015

Phenytoin for Seizures "I had my first ever seizure on 8/4/93, one day before my 24th birthday, out of the 'clear blue.' I was first prescribed 400 mg of Dilantin daily. I experienced muscle spasms/twitches, sleeplessness at night, and sleepiness during my waking hours. I was switched to 400 mg of Phenytek daily. At first, the same symptoms persisted but subsided over time. I have been on both Dilantin and Phenytek for 22 years; currently on Phenytek, and my seizures are controlled, with minor/minimal side effects: occasional muscle twitching and/or headaches remedied with Tylenol. I hold down a full-time job, and I drive, so my #1 priority every night is to take my meds. So far, so good....."

10 / 10
Was this helpful?YesNo
10 Report
  • 2xS...
  • August 3, 2013

For Neurosurgery "Other than some short-term memory issues, I've had no complaints with this medicine other than when my doctor adjusts my dose to where he thinks it should be and not what works for me. I'm currently on 400 mg daily, 200 mg in the morning & 200 mg at dinner time. I'm also maxed on my Keppra, so this is to supplement the additional help needed to control seizures after brain cancer surgery. I am though drowsy a lot, but when I get to the suggested range between 10-20 measurement, I have seizures all too often. I'll stick with the drowsiness!"

9 / 10
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5 Report

Frequently asked questions

  • Che...
  • Taken for 6 months to 1 year
  • December 7, 2012

Phenytoin for Epilepsy "The first 3-4 days made me a bit groggy immediately after taking it. I couldn't drive. Within a week, I adjusted quickly."

10 / 10
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9 Report

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