Mavacoxib: veterinary dose and monograph

At a glance

Drug class

Anti-inflammatory

Also known as

Trocoxil

Species with doses

Dogs

General dose range

2 mg/kg PO day 0, day 14, then monthly (max 7 consecutive doses) — check the species tables for the indication

Routes

PO

Last reviewed

1 October 2026

Indications

• Chronic osteoarthritis pain/inflammation in dogs (monthly dosing for compliance)
• Long-term OA management where daily dosing is impractical

Mavacoxib 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

• Osteoarthritis (monthly): Plumb’s p.760 (Trocoxil label): 2 mg/kg PO immediately before or with the main meal; repeat 14 days later, then monthly; a treatment cycle must not exceed 7 consecutive doses (6.5 months). For dogs ≥12 months needing continuous treatment beyond 1 month. Very long half-life — adverse effects persist; not a daily NSAID. Not in Papich 5e.

Contraindications

Pre-existing GI ulceration, renal or hepatic disease, dehydration/hypovolaemia, bleeding disorders, and concurrent corticosteroids or other NSAIDs (long washout needed because of the persistence). Dogs <12 months or <5 kg. Dogs that have not previously tolerated a daily NSAID. Pregnancy/breeding. Known NSAID hypersensitivity. Cats (NSAID sensitivity).

Species-specific warnings

Dogs: Because of the very long half-life, choose only NSAID-tolerant dogs and counsel owners that adverse effects (GI/renal/hepatic) can be prolonged; avoid around dehydrating illness or surgery.

Adverse effects

• GI: vomiting, diarrhoea, anorexia, ulceration/perforation (PERSISTENT due to long half-life)
• Renal injury (especially with dehydration)
• Hepatotoxicity
• Because effects are long-lasting, adverse reactions can be prolonged

Drug interactions

• Other NSAIDs / corticosteroids: greatly increased GI ulceration risk — and the long half-life mandates a long washout when switching
• ACE inhibitors / diuretics: reduced efficacy and increased nephrotoxicity
• Aminoglycosides / other nephrotoxins: additive renal injury
• Highly protein-bound — displacement interactions

Pregnancy and lactation

Contraindicated in pregnancy/breeding (NSAID fetal effects; long persistence).

Monitoring

• GI tolerance (vomiting, melaena, appetite) — and remember effects persist
• Renal and hepatic values before and periodically during therapy
• Hydration; avoid around dehydrating illness/surgery
• Dog must have a documented history of tolerating a daily NSAID before starting

Toxicity and overdose

Overdose/adverse reaction causes the classic NSAID toxicities (GI ulceration/perforation, acute kidney injury, hepatotoxicity) — but, critically, these can be PROLONGED for weeks because of the long half-life. This persistence is why patient selection (a dog with a proven NSAID-tolerant history) and the 7-dose limit matter.

Management: No specific antidote, and the drug cannot be quickly cleared. Decontaminate if very recent ingestion; aggressive, PROLONGED supportive care — IV fluid diuresis, GI protectants (omeprazole/sucralfate/misoprostol), and monitoring of renal/hepatic values over an extended period (effects outlast a typical NSAID toxicosis). Anticipate a longer recovery than with short-acting NSAIDs.

Clinical pearls

• Monthly NSAID dosing is its big compliance advantage for chronic OA — but the LONG half-life means any adverse reaction lingers for weeks and can't be "stopped" quickly
• Only use in dogs that have ALREADY tolerated a daily NSAID, and respect the 7-consecutive-dose maximum
• Give the second dose at day 14, then monthly; always with food and in a well-hydrated dog
• A long washout is needed before switching to another NSAID/steroid — don't stack

Mechanism of action

Preferentially inhibits cyclo-oxygenase-2 (COX-2), reducing inflammatory prostaglandin synthesis for analgesia/anti-inflammatory effect while largely sparing constitutive COX-1. Its defining feature is pharmacokinetic: an extremely long elimination half-life (weeks, with inter-dog variability) that allows monthly dosing — but also means the drug, and any toxicity, persists long after the last dose.

Formulations and products

• 6 / 20 / 30 / 75 / 95 mg chewable tablet (Trocoxil)
• Trocoxil (Zoetis) — 6 / 20 / 30 / 75 / 95 mg chewable, Chewable tablet

Storage

Chewables: 15–30 °C, dry; keep away from pets (palatable — accidental over-ingestion is especially serious given the persistence).

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.

Other anti-inflammatory drugs

• Flunixin Meglumine
• Grapiprant
• Isoflupredone Acetate
• Ketoprofen
• Meloxicam
• Methylprednisolone Acetate
• Nimesulide
• Phenylbutazone

Frequently asked questions