What You Need to Know About Phenobarbitone

What is phenobarbitone? Why was it prescribed to my pet?

Phenobarbitone (sometimes spelled phenobarbital) is an anti-seizure medication most commonly used to control seizures in pets with epilepsy. It is sometimes also used to control seizures from other causes (e.g. brain tumours).

What forms are available?

Phenobarbitone is available in tablet forms, which are given by mouth. Tablets may be given with or without food.
Always follow your veterinarian’s instructions when giving medication to your pet.
Tablet forms:
•    Phenomav (30mg, 100mg)

Phenobarbitone is available in tablets of different strengths

What side effects are there?

Lethargy and increases in appetite, drinking and urination are common in the first 2-3 weeks of treatment. These signs are usually mild and resolve on their own. They are not a cause for concern unless they are severe, worsen or continue over a long period of time.
Contact your veterinarian if you notice:

•    Weakness
•    Uncoordinated, “drunken” walking
•    Yellow tint to gums or whites of the eyes
•    Pale gums
•    Fever

When should this medication be used very carefully?

Your veterinarian may take additional precautions if your pet: 
•    Has heart, lung or kidney disease
•    Has reduced adrenal gland function
•    Is on other medications 
Precautions may include measures such as closer monitoring or adjustments to medication doses. For advice specific to your pet, please consult your veterinarian.

When should this medication not be used?

Your pet should not receive phenobarbitone if they: 
•    Are allergic to it, or to similar medications
•    Have liver disease

What monitoring is required for pets on phenobarbitone?

It is important to take your veterinarian’s advice and bring your pet for rechecks as needed.
Depending on your pet’s underlying condition, your veterinarian may wish to monitor:
•    For any side effects
•    Seizure frequency, duration and severity
•    Baseline blood tests (particularly to assess the liver)
•    Levels of phenobarbitone in your pet’s blood

Storage and Safety

Keep all medications out of reach of children and pets. Phenobarbitone should be stored at room temperature in a dry place away from light.

Give this medication for as long as your veterinarian specifies and do not discontinue it without first consulting them. If you miss a dose, give it as soon as possible, but if it is near the time of your pet’s next scheduled dose, skip the missed dose and give the scheduled dose. Afterwards, return to your pet’s regular dosing regimen.

Never give a double dose, even if you miss a dose. Contact your veterinarian if you know or suspect that your pet has received an overdose.