Overview of Penicillamine for Dogs and Cats

 Penicillamine, commonly known by the brand names Depen® or Cuprimine®, is used for dogs and cats for the treatment of liver disease, lead poisoning, and kidney and bladder stones.

The accumulation of certain metals within the body can result in severe illness and injury to organs. Removal of these metals can be crucial to the treatment of heavy metal poisonings.

The most common metals that accumulate in the body and that lead to disease (toxicity) are copper, lead, iron and mercury.

Penicillamine belongs to a group of drugs known as chelating agents.

Penicillamine is a byproduct of the antibiotic penicillin; however, penicillamine does not have any antibiotic properties.

Penicillamine is a prescription drug and can only be obtained from a veterinarian or by prescription from a veterinarian.

This drug is not approved for use in animals by the Food and Drug Administration but it is prescribed legally by veterinarians as an extra-label drug.

Brand Names and Other Names of Penicillamine

This drug is registered for use in humans only.

Human formulations: Depen® (Wallace), Cuprimine® (Merck)

Veterinary formulations: None

Uses of Penicillamine for Dogs and Cats

Penicillamine is used in the treatment of liver disease caused by accumulation or abnormal storage of copper.

The drug is also used in the treatment of lead poisoning.

Penicillamine is also used to treat kidney and bladder stones (urolithiasis) due to abnormalities in cystine (an amino acid) metabolism.

Penicillamine is rarely used to treat other heavy metal poisonings (mercury, iron) as there are better chelating agents available for these.

Precautions and Side Effects

While generally safe and effective when prescribed by a veterinarian, penicillamine can cause side effects in some animals.

Penicillamine should not be used in animals with known hypersensitivity or allergy to the drug.

Penicillamine may interact with other medications. Consult with your veterinarian to determine if other drugs your pet is receiving could interact with penicillamine. Such drugs include certain antacids, azathoprine and cyclophosphamide.

Birth defects can occur if penicillamine is administered to pregnant animals.

Nausea and vomiting are the most common adverse effects associated with penicillamine.

Rare adverse effects include fever, kidney impairment, skin reactions or blood disorders.

How Penicillamine Is Supplied

Penicillamine is available in 125 mg and 250 mg tablets or capsules.

Dosing Information of Penicillamine for Dogs and Cats

Medication should never be administered without first consulting your veterinarian.

Penicillamine is typically dosed at 5 to 7 mg per pound (15 mg/kg), orally, twice daily for copper-related toxicity.

For lead poisoning, penicillamine is dosed at a daily dose of 15 to 50 mg per pound (30 to 110 mg/kg) per day. This total dose is divided into three to four doses throughout the day and is supervised closely by a veterinarian.

Penicillamine is typically given for several weeks to months. Some animals may require an even longer course of treatment.

The duration of administration depends on the condition being treated, response to the medication and the development of any adverse effects. Be certain to complete the prescription unless specifically directed by your veterinarian. Even if your pet feels better, the entire treatment plan should be completed to prevent relapse.