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Drug Class: Commonly Known As: Category:
Anticonvulsant Dilantin Adult, Children

Phenytoin - Dosage and How to Use

How should Phenytoin be used?

  • Follow the instructions on your medicine label and take the medicine as prescribed by your doctor.
  • You should take this medication with or after food. Take phenytoin two hours apart from a high-protein meal (e.g. with milk or meat) to make it work better.
  • If you are taking the capsule, swallow capsules whole with a glass of water. Do not take capsules that are discoloured.
  • If you are using oral liquid form/suspension, shake the bottle well before taking. Use a medicine spoon ​or graduated syringe to measure your medication. Do not use household spoons as they may not be accurate.​
  • You may not experience any effect immediately after starting the medication as it may take up to a few weeks before this medication works fully. You should continue to take your medicine regularly as instructed by your doctor even if you feel well. Stopping your medicines without informing your healthcare professional may cause your condition to become worse quickly.
  • Do not stop taking or adjust the dose of this medication without consulting your healthcare professional. Do not change brands or formulations of the medication without informing your healthcare professional.

What should I do if I miss a dose?

If you miss a dose, take the missed dose as soon as you remember. If it is almost time for your next dose, take only the usual dose. Do not double your dose or use extra medicine to make up for the missed dose.

What should I do if I overdose?

  • Updated on Tuesday, June 30, 2020
  • Article contributed by PSS National Medication Information Workgroup PSS National Medication Information Workgroup

The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

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