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Product Details

About Primidone

Primidone is an anticonvulsant that reduces the frequency and severity of seizures, helping to control epilepsy. When Primidone is ingested, it's converted to phenobarbital, which is an anticonvulsant. It works by decreasing nerve impulses in the nervous system, which helps to reduce seizures.
Generally used for dogs only.

Key Benefits of Primidone 

  • Controls severity and frequency of seizures associated with epilepsy
  • Provides an effective means of controlling convulsions associated with infectious neuropathies, such as virus encephalitis and distemper
  • Used for dogs and rarely for cats

Who's Primidone For?

Seizure disorders or convulsions are the physical manifestations of uncontrolled electrical activity in the brain.

Primidone Ingredients

Primidone 250mg

Side Effects and Warnings

If your pet develops any of the following serious side effects, stop giving primidone and seek emergency veterinary medical attention -- an allergic reaction (difficulty breathing, closing of the throat, swelling of the lips, tongue, face, or hives), a rash, worsening of seizures, or fever. Other less serious side effects may occur. Continue to give primidone and talk to your veterinarian if your pet experiences dizziness, poor coordination, drowsiness, blurred vision, irregular movements of the eyes, or nausea and vomiting.

A number of different drugs might have a negative interaction with primidone.

  • Acetazolamide (Diamox), carbamazepine (Tegretol), ethosuximide (Zarontin), and methsuximide (Celontin) may decrease the effects of primidone and require a higher primidone dose.
  • Phenytoin (Dilantin), ethotoin (Peganone), mephenytoin (Mesantoin), and isoniazid may increase the effects of primidone and require a lower primidone dose. Carbamezepine (Tegretol) blood levels may increase when given with primidone.
  • Dosages of carbamazepine may need to be adjusted lower.
  • CNS depressants, valproic acid and chloramphenicol may increase the effect of primidone.
  • Primidone may decrease the effect of coumadin, corticosteroids (such as prednisone), beta blockers (such as atenolol), theophylline and metronidazole.
  • Use with caution when giving primidone with furosemide, griseofulvin or rifampin.

Keep out of the reach of children and other pets.

Primidone Directions

Use as directed by your veterinarian.
Dogs (all weights) The usual dose in dogs is 2.3-6.8 mg per pound of pet's body weight per day in 2 or 3 divided doses. Primidone can be given with food. Allow plenty of water for your pet to drink.

Read the Medication Guide for Primidone