Compare Dilantin vs. Topamax

Head-to-head comparisons of medication uses, side effects, ratings, and more.

Dilantin (Phenytoin)

Prescription only

Qudexy Xr (Topiramate)

Prescription only
Prevents seizures.

Dilantin (Phenytoin) is effective at preventing seizures, but has many drug interactions and side effects. If your blood tests show that you have the right amount of Dilantin (Phenytoin) levels, you’ll have a lower chance of getting side effects.

Prevents seizures and migraine headaches.

Qudexy Xr (Topiramate) is useful for preventing seizures and migraines, and doesn't require blood tests while you're on it.

4.4/ 7 average rating with 56 reviewsforTopamax
Upsides
  • Dilantin (Phenytoin) is effective at preventing seizures, and treating seizures in an emergency.
  • Available in an oral suspension and chewable tablets if you have trouble swallowing capsules.
  • Available as a generic.
  • Used on its own or with other antiepileptic medicines to lower the frequency of seizures, especially for people with tonic-clonic or partial seizures, or Lennox-Gestaut syndrome.
  • Helpful in preventing frequent migraine headaches.
  • Doesn't need routine blood tests.
Downsides
  • Need to get blood tests regularly to make sure Dilantin (Phenytoin) has safe and effective levels in your body.
  • Can cause changes in your appearance, such as unwanted hair growth, enlargement of the gums, and coarsening of your facial features.
  • If you have kidney problems, your dose and kidney function will have to be checked regularly to make sure Dilantin (Phenytoin) levels don’t get too high.
  • Can make many other medicines less effective, including birth control.
  • Can cause sleepiness, speech problems, tingling sensations, and weight loss.
  • A few people will get kidney stones.
  • Not safe to use if you're pregnant.
Used for
Dosage forms
  • Extended release
  • Chewable tablet
  • Liquid
  • Pill
  • Extended release capsule
Price
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$22.42
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$10.2
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Reviews
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56 
52%
think this treatment is worth it
50%
think this treatment works well
36%
think this treatment is a hassle

Have you used Qudexy Xr (Topiramate)?

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Side effects
The Dilantin (Phenytoin) FDA package insert doesn’t have numbers about how common side effects are.
10possible side effects
  • Somnolence
    28%
  • Dizziness
    25%
  • Ataxia
    16%
  • Nervousness
    16%
  • Fatigue
    15%
  • Speech disorders/Related speech problems
    13%
  • Psychomotor slowing
    13%
  • Vision abnormal
    13%
  • Difficulty with memory
    12%
  • Paresthesia
    11%
See more detailed side effects
Risks and warnings
  • Skin reactions

    People of Asian ancestry

  • Serious liver damage

    Starting Dilantin (Phenytoin) within the first two months

  • Cardiovascular risk with fast IV infusions

    Infusing Dilantin (Phenytoin) too fast

  • Suicidal thoughts or behavior

    History of depression

  • Bone fractures due to weakened bones

    History of osteoporosis

    ...and 1 more risk factors

  • Withdrawal seizures

    Stopping Dilantin (Phenytoin) suddenly

See more detailed risks and warnings
  • Suicidal thoughts or behavior

    History of depression

  • Uncontrolled body temperature

    Children

  • Mental changes due to high ammonia

    History of metabolic disorders

    ...and 1 more risk factors

  • Kidney stones

    Low-carb diet

    ...and 2 more risk factors

  • Withdrawal seizures

    Stopping Qudexy Xr (Topiramate) suddenly

See more detailed risks and warnings