Phenytoin

Information about Phenytoin

Phenytoin Uses

Phenytoin is used in the treatment of epilepsy/seizures.

How Phenytoin works

Phenytoin is an antiepileptic medication. It controls seizures or fits by decreasing the abnormal and excessive activity of the nerve cells in the brain.

Common side effects of Phenytoin

Rash, Headache, Dizziness, Insomnia (difficulty in sleeping), Vomiting, Nausea1a, Slurred speech, Vertigo, Confusion, Nervousness, Constipation, Tremor, Altered walking
CONTENT DETAILS
Written By
Dr. Swati Mishra
BDS
Reviewed By
Dr. Khushbu Goel
DM, MD
Last updated
16 Jul 2021 | 02:49 PM (UTC)

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Available Medicine for Phenytoin

Expert advice for Phenytoin

  • Take your medication regularly as directed by your doctor as missing doses can trigger seizures.
  • Do not change the brand of your medicine and make sure that you have sufficient amount of medicine present with you.
  • Some healthy tips to prevent seizures:
    • Practice yoga every day.
    • Get enough sleep at nighttime.
    • Limit the use of screen time such as mobile/laptop.
    • Take your medication on time.
  • It may cause dizziness and sleepiness. Do not drive or do anything that requires mental focus until you know how it affects you.
  • It may increase blood sugar levels. Inform your doctor if you are taking any medicines to treat diabetes.
  • It may cause swollen gum (gum hypertrophy), hence take care of oral or dental hygiene.
  • Talk to your doctor if you notice sudden mood changes or develop suicidal thoughts.
  • Do not stop taking the medication suddenly without talking to your doctor as it may increase the seizure frequency.

Frequently asked questions for Phenytoin

Phenytoin

Q. For how long does Phenytoin stay in your system?

On an average, Phenytoin may stay in your system for 5-6 days. This duration varies from person to person. In some cases, it may stay for about 9-10 days.

Q. What happens if I stop taking Phenytoin?

Suddenly stopping Phenytoin may cause non-stop seizures (called status epilepticus), which can endanger life. Do not stop taking the medicine without consulting your doctor. If required, your doctor will slowly reduce the dose before stopping it completely.

Q. What are the symptoms that occur if I take more than the recommended dose of Phenytoin? Can I die from Phenytoin overdose?

Overdose of Phenytoin may cause jerky movements of the eyes (nystagmus), unclear speech, loss of balance, tremor, muscle stiffness or weakness, nausea, vomiting, lightheadedness, fainting, blurred vision, slow and shallow breathing and even coma. Phenytoin overdose can cause very low blood pressure and respiratory problems. As a result of this, the patient can even die.

Q. Who should avoid taking Phenytoin?

You should not take Phenytoin if you have liver disease, especially if you have a history of developing a liver problem due to Phenytoin. Also, patients taking Delavirdine (a medicine used in the treatment of HIV infection) should not take Phenytoin. Phenytoin may reduce the effectiveness of Delavirdine on HIV and the virus may also become resistant to Delavirdine. It is advised that you inform your doctor if you have any existing heart disorder before you receive Phenytoin.

Q. Can I take Phenytoin with ibuprofen?

Phenytoin can be taken with ibuprofen. No drug-drug interactions have been reported between the two. However, interactions can occur. Please consult your doctor before taking the two medicines together.

Q. What are the effects of Phenytoin on children?

The most common side effects related to Phenytoin in children are jerky movements of the eyes (nystagmus) and overgrowth of the gums. In some children, Phenytoin causes problems with thinking or behavior, mood change, slow or clumsy movements, or a loss of energy. Other side effects from high doses include unsteadiness in the feet and hands, sleepiness, and vomiting. These may be avoidable if the dose is increased slowly. These side effects quickly disappear when the dose is reduced.

Q. Does Phenytoin cause weight gain?

Phenytoin has not been reported to cause weight gain. However, weight loss can occur with longer term use of a higher dose of Phenytoin. Please consult your doctor if you experience weight gain after taking Phenytoin.

Q. Does Phenytoin make you sleepy?

Phenytoin can make you feel sleepy (sedation, somnolence, and drowsiness). Please consult your doctor if you feel very sleepy after taking Phenytoin, especially during the first few weeks of treatment or following a dose increase. Talk to your doctor as you may be advised not to drive or use machines until it is established that your ability to perform such activities is not affected.

Q. Does Phenytoin affect birth control?

Phenytoin does affect birth control. Phenytoin can decrease the effect of oral contraceptives (birth control pills) which can make the contraceptive (birth control) effect unreliable. Please talk to your doctor if you are asked to take the two medicines together as you may need to use extra protection for birth control.

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