Penicillamine (D-Penicillamine): veterinary dose and monograph

At a glance

Drug class

Veterinary drug

Also known as

Cuprimine, Distamine, D-penicillamine

Species with doses

Dogs, Cats, Cattle, Horses, Sheep and Birds

General dose range

10–15 mg/kg PO q12h (empty stomach) — check the species tables for the indication

Routes

PO

Last reviewed

1 October 2026

Indications

• Copper-associated hepatopathy (copper storage disease) — Bedlington Terriers and other breeds
• Lead poisoning (oral chelation alternative)
• Cystine urolithiasis (cystinuria) — dissolution/prevention
• Chronic copper toxicosis management (with low-copper diet ± zinc)

Penicillamine (D-Penicillamine) dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Dogs

• Copper-associated hepatopathy: Papich 5e: 10–15 mg/kg PO q12h, 30 min before a meal; Dobermans 250 mg per dog q12h. Plumb’s p.942: 10–15 mg/kg PO q12h on an empty stomach, starting low (Webb); 15 mg/kg twice daily with pyridoxine, chelating at least 6 months then re-biopsy (Center). Do not give with zinc or mineral supplements. Give with a little food if vomiting, accepting lower absorption.
• Cystine urolithiasis: Plumb’s p.942: 15 mg/kg PO twice daily; give with food or increase gradually if nausea or vomiting occur (Osborne; Lage).
• Lead poisoning (after Ca-EDTA): Plumb’s p.942 (Mount; Nicholson): 30 min before feeding; premedicate with dimenhydrinate 2–4 mg/kg if vomiting.

Cats

• Chelation (lead / copper): Papich 5e (dogs and cats): 10–15 mg/kg PO q12h, 30 min before a meal. Plumb’s p.942 (Reid & Oehme): lead — if blood lead is >0.2 ppm 3–4 weeks after Ca-EDTA, 125 mg per cat PO q12h for 5 days. GI upset common.

Cattle

• Heavy-metal chelation (lead / mercury / copper): Papich 5e (horses and cattle): 10–15 mg/kg PO q12h. Plumb’s p.942: lead or mercury 110 mg/kg PO for 1–3 weeks after clearing the GI tract (Osweiler). FARAD: minimum 21-day slaughter and 3-day milk withdrawal.

Horses

• Heavy-metal chelation: Papich 5e (horses and cattle): 10–15 mg/kg PO q12h.

Sheep

• Copper toxicity: Plumb’s p.942: small ruminants 26–52 mg/kg PO once daily for 6 days (Boileau; Reilly — sometimes successful). FARAD: minimum 21-day slaughter and 3-day milk withdrawal.

Buffalo

No buffalo-specific doses are on file, so buffalo are dosed as cattle.

• Heavy-metal chelation (lead / mercury / copper): Papich 5e (horses and cattle): 10–15 mg/kg PO q12h. Plumb’s p.942: lead or mercury 110 mg/kg PO for 1–3 weeks after clearing the GI tract (Osweiler). FARAD: minimum 21-day slaughter and 3-day milk withdrawal.

Birds

• Lead poisoning (adjunct): Plumb’s p.942 (Jones 2007): 55 mg/kg PO q12h; Ca-EDTA plus penicillamine until signs resolve, then penicillamine for 3–6 weeks, has been suggested as the best regimen.

Contraindications

Penicillin hypersensitivity (cross-reactivity possible). Pre-existing significant renal disease/proteinuria, or blood dyscrasias (penicillamine can cause immune-complex nephropathy and cytopenias). Pregnancy (teratogenic). Concurrent mineral supplements/antacids at the same time (reduce chelation). Known hypersensitivity.

Species-specific warnings

Dogs: For copper hepatopathy it is long-term therapy — monitor liver/copper status, urine protein and CBC; combine with a low-copper diet and consider zinc (dosed at a separate time).

Adverse effects

• GI upset (vomiting, anorexia) — common
• Immune-mediated effects with chronic use: proteinuria/nephropathy, skin reactions, blood dyscrasias
• Pyridoxine (vitamin B6) depletion (chronic use)
• Taste changes / hypersalivation

Drug interactions

• Oral minerals (zinc, iron, calcium) / antacids / food: bind penicillamine and reduce absorption and chelation — separate dosing
• Other nephrotoxic/marrow-suppressive drugs: additive risk
• Zinc therapy (for copper disease): give at a different time (zinc reduces penicillamine absorption but both are used in copper management)
• Pyridoxine: supplement on long-term therapy (penicillamine is a B6 antagonist)

Pregnancy and lactation

Contraindicated/avoid in pregnancy (teratogenic — connective-tissue defects).

Monitoring

• Hepatic copper / liver values (copper hepatopathy) — response over months
• Urine protein (UPC) and CBC periodically (immune-mediated nephropathy/cytopenias)
• GI tolerance; pyridoxine status on long-term use
• Urinary cystine / stone recurrence (cystinuria); blood lead (lead poisoning)

Toxicity and overdose

Acute toxicity is mainly GI (vomiting/anorexia). Chronic therapy carries idiosyncratic IMMUNE-MEDIATED risks — proteinuric nephropathy (immune-complex), blood dyscrasias (thrombocytopenia, neutropenia), and skin/mucocutaneous reactions — plus pyridoxine depletion. These warrant periodic urine-protein and CBC monitoring.

Management: No specific antidote. Discontinue; supportive care (fluids, anti-emetic); monitor renal function/urine protein and CBC. Supplement pyridoxine. Manage immune-mediated effects by stopping the drug ± immunosuppression. Decontaminate large recent ingestions.

Clinical pearls

• The chelator for COPPER storage hepatopathy (classically Bedlington Terriers) — lowers hepatic copper over months alongside a low-copper diet ± zinc
• Give on an EMPTY stomach and separate from mineral supplements/food (they block absorption and chelation)
• Also dissolves/prevents CYSTINE stones and chelates lead
• Watch for the chronic immune-mediated effects (proteinuria, cytopenias) — monitor UPC and CBC; supplement pyridoxine; avoid in pregnancy

Mechanism of action

A degradation product of penicillin that acts as a chelator: its thiol and amino groups bind copper, lead and other metals to form stable water-soluble complexes excreted in urine, lowering hepatic copper (and body lead) burdens. For cystinuria, its thiol group reacts with cysteine to form a soluble penicillamine-cysteine disulphide, increasing urinary cystine solubility and dissolving/preventing cystine stones. It also has some immunomodulatory activity (basis of its rare immune-mediated side effects).

Formulations and products

• 125 / 250 mg capsule/tablet (Cuprimine)
• Cuprimine / Distamine — 125 / 250 mg capsule, Capsule (human-label)

Storage

Capsules/tablets: 15–30 °C, dry, protect from light/moisture.

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

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• Oxytocin
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• Phenylpropanolamine (PPA)
• Phytonadione (Vitamin K1)

Frequently asked questions