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Phenobarbitone

Drug Class: Commonly Known As: Category:
Anticonvulsant Children

Phenobarbitone - What is it for

Phenobarbitone is used to control seizures and other problems related to the nervous system.

Phenobarbitone - Side Effects, Precautions, and Contraindications

What side effects can Phenobarbitone cause?

Generally, the common side effects tend to occur at the beginning of treatment. Such side effects may include:

  • Drowsiness, dizziness, and headache, tiredness. Be careful when you are administering over-the-counter medicines. Medicines for cold and allergy may add on to the drowsiness. Be sure to supervise your child when he/she is involved in activities such as cycling or swimming.
  • Behaviour changes such as excitement, restlessness, depression and vivid nightmares.
  • Nausea, vomiting, upset stomach and constipation. If the medication upsets the stomach, take it with food but do not take it with carbonated drinks.
  • Poor muscle coordination, insomnia, hallucinations (see and hear things that do not exist)

Inform your doctor if any of the above side effects lasts for more than a few days or if they become serious or bothersome.

Rare but serious effects may sometimes occur. Contact your doctor as soon as possible if you notice any of the following:

  • Yellowing of the skin or eyes
  • Severe skin rash, itchy or peeling skin
  • Unusual bruises or bleeding
  • Prolonged fever, sore throat, mouth sores
  • Breathing difficulties

Inform your doctor if you notice any other unusual symptoms. Always discuss with your doctor or pharmacist if you or your child has any problems or difficulties during or after taking phenobarbitone.


Before taking Phenobarbitone, what precautions must I follow?

What food or medicine must I avoid when I take Phenobarbitone?

Phenobarbitone - Dosage and How to Use

How should Phenobarbitone be used?

Phenobarbitone is usually taken 1 to 2 times a day. The doctor may start you or your child on a low dose and then slowly increase the dose. Follow the instructions on the label carefully and ask your pharmacist or doctor if you are unsure.

Do not take this medication more often than directed and do not stop unless instructed by the doctor. Stopping this medicine too rapidly can increase the risk of seizures or fits.

Do not change brands or dosage forms without informing your doctor.

Oral liquid form

  • Shake well before using. Use a medicine spoon or the graduated syringe provided to measure your medicine. Do not use household spoons as they may not be accurate.

Tablet form

  • Swallow the tablets with a glass of water. If you or your child is unable to swallow the tablet, you may crush it and add it to small amount of food (i.e. yogurt, ice-cream, syrup) before administering it. Phenobarbitone can be taken with or without food.

What should I do if I miss a dose?

Administer the dose as soon as you remember and then continue to take it as you normally would. However, if it is almost time for the next dose, skip the missed dose and give the next dose at the usual time.

Do not double or increase the dose.

If you or your child has missed more than two doses or you are not sure of what to do, consult your doctor or pharmacist.

If you or your child has less than two weeks supply of medication, please ensure that you have made an appointment with your neurologist or made arrangements to collect more medication.

What should I do if I overdose?

Phenobarbitone - Handling and Storage

How should I handle Phenobarbitone safely?

How should I store Phenobarbitone?

Keep away from children;#Keep in a cool, dry place, away from direct sunlight;#Store at room temperature;#

How should I dispose of Phenobarbitone safely?

Phenobarbitone - Additional Information

Check with your doctor or pharmacist before taking other medicines, supplements or herbal products.

If you or your child sees another doctor, inform him/her that you or your child is taking phenobarbitone before your doctor prescribes any other medications.

  • Updated on Wednesday, October 4, 2017
  • This article is contributed by Department of Pharmacy KK Women's and Children's Hospital

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