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CONTRIBUTOR(S): Vetstream Ltd, Gigi Davidson, Fear Free,

Medication: Diltiazem

Medication: Diltiazem

Your cat has been prescribed diltiazem for the treatment of an irregular/fast heart beat or to control high blood pressure.

Key points:
• Anti-arrhythmic medication.
• Dosage: depending on the dosage form, one to three times in 24 hours. 

This information sheet is designed to help answer commonly asked questions and help you give the medication safely and effectively to your pet. It does not contain all available information for this medication. If you have other questions or need more information, contact your veterinarian or pharmacist.Always follow the dosing instructions provided by your veterinarian.

Name, Brand names, Class of medication and Storage

Name

  • Diltiazem (Dil-ty-a-zim).

Brand name

  • There are no licensed veterinary products for cats in the UK or US. Your veterinarian will explain off-license or extralabel use of diltiazem.
  • Human dosage forms are available in immediate release dosage forms (must be given three times daily) or in delayed release dosage forms (given one to two times daily).

Class of medication

  • Anti-arrhythmic.

Storage

  • Store at room temperature (20-25°C/ 68-77°F) protected from heat, light, and moisture.

Why has my cat been prescribed diltiazem?

Your veterinarian has prescribed diltiazem for the treatment of a heart or blood pressure problem.

How is the medication given?

Diltiazem is given orally (as tablets or capsules) with or without food. It is administered one to three times in every 24 hours depending on the dosage form used. Diltiazem for immediate release is given every 8 hours. Your veterinarian may prescribe a long-acting human capsule that contains individual tablets or granules within the capsule. You may be instructed to open the capsule and administer a specific number of the tablets or a calibrated measure of granules at each dosage. It is very important that you and your pharmacist understand which dosage form your veterinarian is prescribing.

Are there any side-effects or drug interactions?

Diltiazem has been reported to cause lethargy, constipation, vomiting, anorexia, skin problems and heart problems in cats. As there are no licensed veterinary products for cats, information is limited to advise further in this species. Use cautiously in animals with liver or kidney disease.

Diltiazem is used with care in cats with controlled heart failure, especially those who are receiving B-blockers.

Diltiazem should be used only if the benefit outweighs risk in pregnant or nursing cats. Diltiazem interacts with many drugs.  Tell your veterinarian about any medications or supplements that your cat is receiving at home. Recommendations on the interaction between diltiazem and other medicaments are derived from studies in species other than cats, but caution is required if your pet is already taking similar drugs, anticonvulsant drugs, immunosuppressants, certain antibiotics or requires anesthesia.

How long will my cat need to receive this medication?

Diltiazem tablets and capsules should be administered according to your veterinarian’s instructions. Treatment is usually life-long.

How should I dispose of this medication if I don’t use it all?

Dispose of any unused diltiazem safely – do not flush down the toilet or sink. Ask your veterinary team if they take back medication for disposal. Do not save diltiazem for future use or give to other pets.

What if I miss a dose or give an extra dose?

If you miss a dose, give the dose as soon as possible but do not give a double dose. Make sure the dose given does not exceed the total recommended dose in any 24-hour period.

My cat is unwell, should I still give the drug?

If your pet is unwell, contact your veterinarian for advice.

What should I do if this medication is accidentally given to another pet or taken by a human?

Diltiazem should only be given to the cat that it has been prescribed for. If accidentally given to other pets, contact your veterinarian for advice.

If accidentally consumed by a human, speak to your primary care physician or poison control center.

Will my cat need to be monitored while on diltiazem?

Your cat will require regular checks to monitor heart rate, rhythm, and blood pressure. Your cat may require blood tests to monitor liver and kidney function whilst on diltiazem.

Further information

If you have any concerns, further information on diltiazem can be found on the package insert or by contacting your veterinarian.

Europe & UK

  • There are no veterinary drugs containing diltiazem licensed for use in cats in the UK. Your veterinarian may prescribe a human drug containing diltiazem or a drug licensed for use in another species and will be able to explain the use of off-license medications to you.

US

  • There are no veterinary drugs containing diltiazem licensed for use in cats in the US. Your veterinarian may prescribe a human drug containing diltiazem or a drug licensed for use in another species and will be able to explain the use of off-license medications to you.
  • Human Dosage Forms (US):
    • Diltiazem generic tablets 30 mg, 60 mg, 90 mg, 120 mg for immediate release.
    • Dilacor-XR® 120 mg, 180 mg, 240 mg, 360 mg Capsules (containing multiple individual tablets) for delayed release.
    • Cardizem CD® 120 mg, 180 mg, 240 mg, 360 mg Capsules (containing granules) for delayed release.

Always follow the recommended dosage and contact your veterinary team or pharmacist if you have any questions regarding your cat’s medication.

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