Phenobarbitone is used to control some types of seizures, (commonly known as fits).

​What is this medication used ​​for

Phenobarbitone is used to control some types of seizures, (commonly known as fits).


Dosage and ​How to Use

  • Do not stop taking your medicines without checking with your doctors.
  • 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.
  • Follow the dose given on your medicine label. Do not take more or less of it or take it more often than that instructed by your doctor.
  • You should continue to take your medicines regularly as instructed by your doctor even if you feel well. Stopping your medicines without informing your doctor may cause your condition to become worse quickly.
  • Phenobarbitone can be taken with or without food. You can take it with food if you experience stomach upset.


Side Effects, Precautions, Contraindication​

What are the possible side effects of the medicine?

The common side effects of phenobarbitone include:

  • Feeling drowsy or dizzy, headache
  • Feeling tired and restless. Some patients experience excitement.
  • Nausea, vomiting, stomach upset, constipation
  • Difficulty sleeping, hallucinations (seeing or hearing things that are not present), vivid dreams
  • Feeling clumsy

These symptoms may happen but should get better over time. Check with your doctor if any of these symptoms are serious or do not go away.

If the following serious side effects happen, you should check with your doctor immediately:

  • Fever, sore throat or mouth ulcers that do not go away
  • Yellowing of eyes or skin (Jaundice)
  • Red skin rash that forms blisters or peels
  • Difficulty in breathing
  • Unusual bleeding or bruising

How do I know if I am allergic t​​​o this medicine?

The symptoms of a drug allergy include one or more of the following:

  • Swollen face/eyes/lips 
  • Difficulty in breathing 
  • Itchy skin rashes over your whole body

If you experience any of these symptoms, you should stop your medicine immediately and see your doctor.

What precautions should I follow when taking the medicine?

  • You should inform your doctor if you have liver or kidney problems before starting on phenobarbitone. 
  • Be careful when driving or operating machinery as this medicine may cause drowsiness. Do not take alcohol and other medicines that make you less alert. 
  • If you are taking other medicines, phenobarbitone may affect how they work. Please see your doctor or pharmacist before using any other medicines, including over-the-counter medicines, vitamins and herbal products. Please make sure that the doctor who treats you knows that you are on phenobarbitone. 
  • Phenobarbitone can decrease the effectiveness of medicines that prevent pregnancy. Check with your doctor about additional or other methods of birth control.
  • You must tell your doctor if you are allergic to any other medicines, or if you develop an allergy while taking this medicine.
  • If you are pregnant or planning to get pregnant or are breastfeeding, you should inform your doctor.
  • See your doctor immediately if your seizures get worse or become different after you start using this medicine.


Handling and Storage

  • Keep your medicines in the original container or packaging, tightly closed or sealed in a cool and dry place, away from direct sunlight.
  • Keep the medicine out of reach of children.
  • Throw away all expired medicines.

​​This medicine has been proven to be safe and effective, but it can cause serious injury if a mistake happens while taking it. This means that it is very important for you to know about this medicine and take it exactly as directed.​​

This article answers some common questions about this medicine. It does not contain all the available information. It also does not take the place of talking to your doctor or pharmacist.​



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