General Description: Primidone is an anticonvulsant used long-term to reduce the frequency and severity of seizures and control epilepsy in dogs. Primidone is used in dogs only. Available as 250 mg scored tablets by prescription from your veterinarian.

What is this drug?

An anticonvulsant
Given by mouth
Reasons for prescribing:

Used to control the frequency and severity of seizures associated with epilepsy in dogs
Also used to control seizures associated with various infections such as viral encephalitis and distemper
Rarely used in cats
What dogs/cats should not take this medication?

Dogs with pre-existing liver disease
Use with extreme caution in dogs suffering from conditions like dehydration, anemia, Addison’s disease, heart, kidney or respiratory diseases
Not for use in pregnant or nursing animals
If your pet has had an allergic reaction to primidone, barbiturates or like products before

Read and follow the label carefully.

Give the exact amount prescribed and only as often as directed. It is usually giventwo or three times a day and can be used long-term.

Ideally, give the medication at the same time(s) daily.

It is important not to skip doses as this may cause a seizure. Do not skip doses or stop giving the medication without consulting your veterinarian.

Primidone may be given whole, or crushed and mixed with food.

It will take several days to get a high enough level of this medication in the blood stream to control seizures. Monitor extra closely at this time. Blood levels will stabilize within 2-3 weeks.

Baseline blood work to assess your pet’s health before starting this drug is recommended. Periodic blood work to monitor its effect is also advised if long-term therapy is necessary. Dose adjustments will be made based upon the blood results and an assessment of how your dog is responding clinically. Blood will be drawn 4-6 hours after the morning dose was given. You may want to keep this in mind when you schedule your follow-up appointments.

Ensure that your pet has access to plenty of fresh, clean drinking water.

Call ahead for refills.

What if a dose is missed?

If a dose is missed, give it as soon as you can. If it is time already for the next dose, skip the missed dose and go back to the normal schedule. Do not give two doses at the same time.

What to tell/ask veterinarian before giving medication?

Talk to your veterinarian about:

When will your pet need to be rechecked
What tests may need to be performed prior to and during treatment with this drug
What are the risks and benefits of using this drug
Tell your veterinarian about:

If your pet has experienced side-effects on other drugs/products
If your pet has experienced digestive upset now or ever
If your pet has experienced liver or kidney disease now or ever
If your pet has experienced any other medical problems or allergies now or ever
All medicines and supplements that you are giving your pet or plan to give your pet, including those you can get without a prescription. Your veterinarian may want to check that all of your pet’s medicines can be given together.
If your pet is pregnant or nursing or if you plan to breed your pet
Storage and Warnings:

Store in a tight, light resistant, childproof container in a cool, dry place at room temperature away from heat and direct sunlight.

Keep this and all medication out of reach of children and pets.

Call your physician immediately if you accidentally take this product.

Potential side effects:

Restlessness, anxiety, drowsiness, dizziness, increased appetite, thirst, fever, blurred vision, irregular back and forth movements of the eyes, nausea or vomiting
If your pet experiences an allergic reaction (difficulty breathing, closing of the throat, swelling of the lip, tongue, face, rash, or hives), contact your veterinarian immediately
Possible long term use effects: increased water consumption, urination and appetite, dermatitis and anemia
Liver damage is possible. Periodic blood tests may be advised to monitor liver function. Simultaneous administration of SAMe (S-adenosylmethionine) may be a good supportive supplement.
If these symptoms persist, your pet has additional seizures or you notice anything else unusual, contact your veterinarian
Can this drug be given with other drugs?

Yes, but possible interactions may occur with acetazolamide, beta blockers, carbamezepine, chloramphenicol, corticosteroids, coumadin, ethotoin, ethrosuximide, furosemide, griseofulvin, isoniazid, mephenytoin, methsuximide, metronidazole, phenytoin, rifampin, theophylline and valproic acid
If your pet experiences any unusual reactions when taking multiple medications, contact your veterinarian.

Contact your veterinarian immediately if pet eats more than the prescribed amount.

What else should I know?

Notify your veterinarian if your animal’s condition does not improve or worsens despite this treatment.

As with all prescribed medicines, primidone should only be given to the pet for which it was prescribed. It should be given only for the condition for which it was prescribed.

This is just a summary of information about primidone. If you have any questions or concerns about primidone or the condition it was prescribed for, contact your veterinarian.

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