Auranofin
Also known as: Crisinor · Crisofin · Goldar · Ridauran · SKF-39162 · SKF-D-39162
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Immune-mediated arthropathies and dermatopathies | 0.05-0.2 mg/kg (up to 9 mg/day total dose) | PO | q12h | — | 🌎 NA |
| Treatment of pemphigus complex (with corticosteroids) | 0.12-0.2 mg/kg | PO | twice daily | — | 🌎 NA |
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Rescue drug for feline pemphigus and for idiopathic dermatoses and plasma cell pododermatitis/stomatitis | 0.2-0.3 mg/kg | PO | twice daily | — | 🌎 NA |
- Rescue drug for feline pemphigus and for idiopathic dermatoses and plasma cell pododermatitis/stomatitis: Must be reformulated for accurate dosing.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Auranofin is an orally administered gold salt used in veterinary medicine primarily for its immunomodulatory properties (a practice known as chrysotherapy).
- Clinical Use: Historically used for immune-mediated conditions like pemphigus foliaceus and idiopathic polyarthritis in dogs and cats.
- Efficacy vs. Toxicity: It is generally considered less toxic but also less efficacious than injectable gold compounds (e.g., aurothioglucose).
- Modern Context: Its use has largely been supplanted by newer, safer, and more effective immunosuppressants (e.g., cyclosporine, mycophenolate).
- Compounding Required: Due to the commercial human capsule size (3 mg), it almost always requires compounding for accurate dosing in small animals.
Mechanism of action
The exact mechanism of gold salts is not fully elucidated, but they possess anti-inflammatory, antirheumatic, and immunomodulating effects.
- Macrophage Inhibition: Auranofin is taken up by macrophages → inhibits phagocytosis and suppresses lysosomal enzyme activity.
- Mediator Suppression: Inhibits the release of histamine and the production of prostaglandins.
- T-Cell Modulation: Selectively suppresses helper T-cells (CD4+) without significantly affecting suppressor T-cell populations, thereby dampening the autoimmune response.
Safety & warnings
Contraindications
- Systemic Lupus Erythematosus (SLE) - may exacerbate signs
- Pregnancy (known teratogen and maternotoxic)
Adverse effects
- Immune-mediated thrombocytopenia (dose-dependent)
- Hemolytic anemia
- Leukopenia
- Gastrointestinal disturbances (particularly diarrhea, dose-dependent)
- Renal toxicity (proteinuria)
- Hepatotoxicity (increased liver enzymes)
- Dermatosis
- Corneal ulcers
Precautions
High-Risk Therapy: Should only be administered when other less expensive and toxic therapies are ineffective. Veterinarians and owners must be willing to accept associated risks and expenses.
- Teratogenicity: Known teratogen and maternotoxic; do not use during pregnancy unless risks are accepted.
- Nursing: Gold is excreted in milk and persists even after discontinuation. Switch to milk replacer if the dam is treated.
- Toxicity Monitoring: Intensive ongoing monitoring is required due to potential for severe hematologic, renal, and hepatic toxicity.
Drug interactions
Safety when used with these agents has not been established; use with caution.
Increased potential for hematologic or renal toxicity; use with gold salts is not recommended.
Increased potential for hematologic or renal toxicity; use with gold salts is not recommended.
Monitoring
- Hepatic function tests (baseline, monthly for 2-3 months, then every other month)
- Renal function tests including urinalysis (baseline, monthly for 2-3 months, then every other month)
- CBC with platelet counts (baseline, monthly for 2-3 months, then every other month). Note: eosinophilia may denote impending reactions.
Pharmacokinetics
Absorption
Absorbed when given by mouth (20-25% of the gold) primarily in the small and large intestines.
Distribution
Moderately bound to plasma proteins. Crosses the placenta and is distributed into maternal milk. Highest levels found in kidneys, spleen, lungs, adrenals, and liver. Accumulation does not appear to occur (unlike parenteral gold salts).
Elimination
About 15% of an administered dose (60% of the absorbed dose) is excreted by the kidneys, the remainder in the feces.
Overdose
Very limited data is available. The minimum lethal oral dose in rats is 30 mg/kg.
- Decontamination: Gut-emptying protocols should be employed after an acute overdose when applicable.
- Antidotes: Chelating agents (e.g., penicillamine, dimercaprol) have been used for severe toxicities, but their use is controversial.
Available products
Formulations
- Capsules
Human-labeled
- Auranofin Capsules: 3 mg; Ridaura® (SK-Beecham)
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store capsules in tight, light-resistant containers at room temperature. After manufacture, expiration dates of 4 years are assigned to the capsules.
Client information
Important: This medication requires strict adherence to dosing and monitoring schedules.
- Patience is Key: It may take several months of consistent dosing before a positive response is seen in your pet.
- Strict Schedule: Commitment to the twice-daily dosing schedule is essential for success.
- Monitoring: Frequent blood and urine tests are absolutely necessary to catch potential severe side effects (like kidney, liver, or bone marrow issues) early.
- Side Effects: Watch closely for diarrhea, lethargy, or unusual bleeding/bruising. Contact your veterinarian immediately if these occur. Diarrhea is a common dose-dependent side effect.
- Pregnancy Warning: This drug can cause birth defects. Do not handle if you are pregnant, and do not use in breeding, pregnant, or nursing pets.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.