Tepoxalin
Also known as: Zubrin · ORF-20485 · RWJ-20485
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 |
|---|---|---|---|---|---|
| Pain and inflammation associated with osteoarthritis | 20 mg/kg PO (or 10 mg/kg PO) on first day; subsequently give 10 mg/kg PO once daily | PO | q24h | Based on clinical response and patient tolerance | 🌎 NA |
- Pain and inflammation associated with osteoarthritis: On first day of treatment give 20 mg/kg PO (or 10 mg/kg PO); subsequently give 10 mg/kg PO once daily.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Tepoxalin is a unique dual inhibitor of both cyclooxygenase (COX) and lipoxygenase (LOX) pathways. It is primarily indicated for the management of pain and inflammation associated with canine osteoarthritis.
- Available as a rapidly disintegrating tablet (melt-in-mouth), making it highly advantageous for dogs that are difficult to pill.
- Because of its inhibitory effects on leukotrienes, there has been interest in its potential as an adjunctive treatment for allergic conditions in dogs.
- Clinical Pearl: Despite the theoretical gastrointestinal protection from LOX inhibition, clinical data suggests tepoxalin may cause more vomiting and diarrhea compared to some other modern FDA-approved COX-2 selective NSAIDs.
Mechanism of action
Tepoxalin blocks the arachidonic acid cascade at two key points:
- Cyclooxygenase (COX-1 and COX-2) → Decreases production of pro-inflammatory prostaglandins (mediators of pain, hyperpyrexia, and inflammation).
- 5-Lipoxygenase (5-LOX) → Decreases production of leukotrienes (e.g., LTB4).
Pharmacological Note: LTB4 is a potent chemoattractant for neutrophils and contributes to GI mucosal damage by increasing cytokine production and release of proteinases. By inhibiting LOX, tepoxalin theoretically mitigates the GI ulcerogenic effects typically seen with COX-1 inhibition, though clinical GI side effects still occur. LOX inhibition in dogs persists for only about 6 hours after dosing.
Safety & warnings
Contraindications
- Prior hypersensitivity reactions to tepoxalin
- Active gastrointestinal ulcers
- Dogs weighing less than 3 kg (cannot be accurately dosed)
- Dogs less than 6 months old (safety not established)
Adverse effects
- Diarrhea
- Vomiting
- Anorexia/inappetence
- Enteritis
- Lethargy
- Incoordination (<1%)
- Incontinence (<1%)
- Increased appetite (<1%)
- Eating grass (<1%)
- Flatulence (<1%)
- Hair loss (<1%)
- Trembling (<1%)
Precautions
Use with caution in patients with impaired hepatic, cardiovascular, or renal function, or those at risk for developing nephrotoxic effects associated with NSAIDs (e.g., dehydrated patients or those on concomitant diuretic therapy). Safety has not been determined in pregnant, breeding, or lactating dogs; use with caution and informed consent. Discontinue if signs of inappetence, vomiting, fecal abnormalities, anemia, icterus, or lethargy are observed.
Drug interactions
May increase the risk of gastrointestinal toxicity (e.g., ulceration, bleeding, vomiting, diarrhea)
May increase the occurrence of gastric ulceration; avoid concomitant use
NSAIDs may increase serum levels of digoxin
May increase plasma levels of tepoxalin (extrapolated from human celecoxib data)
NSAIDs may reduce saluretic and diuretic effects
Serious toxicity has occurred with concomitant NSAID use; use with extreme caution
May enhance the risk of nephrotoxicity
May increase the risk of gastrointestinal toxicity (e.g., ulceration, bleeding, vomiting, diarrhea)
Tepoxalin is highly protein bound (98-99%); may displace warfarin and increase bleeding risk. Monitor closely.
Monitoring
- Clinical efficacy (improvement in mobility/pain)
- Baseline and periodic CBC
- Chemistry panel (including bilirubin and serum creatinine)
- Signs associated with adverse effects (GI effects, appetite, vomiting, diarrhea, etc.)
Pharmacokinetics
Half-life
Absorption
Readily absorbed after oral administration. Peak levels occur between 2-3 hours post-dose. The presence of food in the gut increases bioavailability.
Distribution
Tepoxalin and its active metabolite (tepoxalin pyrazole acid) are highly bound to plasma proteins (98-99%).
Metabolism
Rapidly metabolized to several metabolites, including the active metabolite tepoxalin pyrazole acid.
Elimination
Metabolites are eliminated primarily in the feces; only 1% of the drug is eliminated in the urine.
Overdose
Information on acute overdosage is limited. Chronic overdosage (300 mg/kg/day for 6 months) in dogs caused decreases in total protein, albumin, and calcium concentrations, with gastric lesions noted at necropsy.
An acute overdose may cause significant GI distress, ulceration, and GI bleeding.
- Treatment: Treat supportively. Monitor CBC, hydration status, renal function, and for evidence of GI bleeding. Contact an animal poison control center for further guidance.
Available products
Formulations
- Rapidly-disintegrating oral tablets
Veterinary
- Tepoxalin Oral (rapidly-disintegrating) Tablets: 30 mg, 50 mg, 100 mg, 200 mg in foil blisters (Zubrin)
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Tablets should be kept in their foil blister packs until used and stored at temperatures between 2-30°C (36-86°F).
Client information
- Administration: Place the tablet directly into your dog's mouth and hold the mouth closed for approximately 4 seconds. The tablet is designed to disintegrate rapidly in saliva, preventing the dog from spitting it out.
- Food: Give this medication with food to improve absorption and potentially reduce stomach upset.
- Hydration: Ensure your dog always has access to fresh water. Dehydration increases the risk of kidney side effects.
Important: Stop the medication immediately and contact your veterinarian if you notice severe or persistent vomiting, diarrhea, black/tarry stools, loss of appetite, lethargy, or yellowing of the gums/eyes (jaundice).
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.