Tepoxalin
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.
Mecanismo: 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.
Dosificación por especie
- 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 · On first day of treatment give 20 mg/kg PO (or 10 mg/kg PO); subsequently give 10 mg/kg PO once daily.
Las dosis son una referencia clínica para veterinarios colegiados. Confirme siempre con la ficha técnica vigente y el paciente individual.
Vías de administración
Contraindicaciones
- 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)
Efectos adversos
- Diarrhea
- Vomiting
- Anorexia/inappetence
- Enteritis
- Lethargy
- Incoordination (<1%)
- Incontinence (<1%)
- Increased appetite (<1%)
- Eating grass (<1%)
- Flatulence (<1%)
- Hair loss (<1%)
- Trembling (<1%)
Interacciones farmacológicas
- Aspirin · May increase the risk of gastrointestinal toxicity (e.g., ulceration, bleeding, vomiting, diarrhea)
- Corticosteroids · May increase the occurrence of gastric ulceration; avoid concomitant use
- Digoxin · NSAIDs may increase serum levels of digoxin
- Fluconazole · May increase plasma levels of tepoxalin (extrapolated from human celecoxib data)
- Furosemide · NSAIDs may reduce saluretic and diuretic effects
- Methotrexate · Serious toxicity has occurred with concomitant NSAID use; use with extreme caution
- Nephrotoxic Drugs (e.g., aminoglycosides, amphotericin B) · May enhance the risk of nephrotoxicity
- Other NSAIDs · May increase the risk of gastrointestinal toxicity (e.g., ulceration, bleeding, vomiting, diarrhea)
- Warfarin · Tepoxalin is highly protein bound (98-99%); may displace warfarin and increase bleeding risk. Monitor closely.
Monitorización
- 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.)
Sobredosis
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.
La referencia de fármacos de VetSheet está destinada a veterinarios colegiados como apoyo a la decisión clínica, no sustituye el juicio profesional ni la ficha técnica vigente del fabricante.