Firocoxib: veterinary dose and monograph

At a glance

Drug class

Anti-inflammatory

Also known as

Previcox, Equioxx

Species with doses

Dogs, Cats and Horses

General dose range

0.1–5 mg/kg PO q24h — check the species tables for the indication

Routes

PO, IV

Last reviewed

1 October 2026

Indications

• Canine osteoarthritis pain and inflammation
• Post-operative pain (soft-tissue / orthopaedic)
• Equine musculoskeletal pain and lameness

Firocoxib 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 / post-op pain: Papich 5e and Plumb’s p.524 (Previcox label): 5 mg/kg PO once daily, dosed in half-tablet increments, with or without food.

Cats

• Single-dose analgesia (limited data): Papich 5e: 1.5 mg/kg PO once; long-term safety in cats has not been determined. Plumb’s p.524: not currently recommended in cats without further safety data.

Horses

• Musculoskeletal pain: Papich 5e and Plumb’s p.524 (Equioxx paste label): 0.1 mg/kg PO once daily for up to 14 days.
• Musculoskeletal pain (IV injection): Papich 5e (Equioxx injection): 0.09 mg/kg IV once daily (2 mL per 1000 lb). Switch to the oral paste for longer courses.

Contraindications

Pre-existing GI ulceration, renal or hepatic impairment, dehydration / hypovolaemia. Do NOT combine with corticosteroids or another NSAID. Not for cats. Avoid in pregnancy / lactation and in animals < 7 months (dog).

Species-specific warnings

Cats: Not labelled for cats — feline NSAID dosing is very different; use a cat-licensed product (robenacoxib / meloxicam) instead.

Adverse effects

• GI: vomiting, diarrhoea, inappetence, ulceration
• Renal: azotaemia, especially with hypotension / dehydration
• Hepatopathy (idiosyncratic)

Drug interactions

• Other NSAIDs or corticosteroids: markedly increased risk of GI ulceration / perforation — never combine; observe a 5–7 day washout when switching
• ACE inhibitors / diuretics (furosemide): NSAIDs blunt their efficacy and raise the risk of renal injury in volume-depleted patients
• Aminoglycosides and other nephrotoxins: additive kidney risk
• Highly protein-bound drugs (warfarin, phenytoin): possible displacement and enhanced effect

Pregnancy and lactation

Not recommended in pregnant, breeding or lactating animals — NSAIDs can interfere with implantation, prostaglandin-dependent ductus arteriosus closure and parturition; safety not established.

Monitoring

• Baseline then periodic renal (BUN / creatinine, urine) and hepatic (ALT / ALP) values on chronic therapy
• Appetite, vomiting and faecal colour — stop at the first sign of GI bleeding
• Hydration and blood pressure before and during NSAID use

Toxicity and overdose

Overdose or chronic exposure causes GI ulceration / perforation, acute kidney injury and, less commonly, idiosyncratic hepatopathy. Risk escalates with dehydration, hypotension, advanced age and concurrent NSAID / steroid use. Flavoured chewables invite accidental over-ingestion by dogs.

Management: Discontinue immediately. GI protection (omeprazole ± sucralfate ± misoprostol), IV fluids to preserve renal perfusion, and supportive care for ulceration. Monitor renal and hepatic values and faeces for melaena. No specific antidote; recent large ingestion — consider emesis / activated charcoal.

Clinical pearls

• Mind the 50-fold species gap — 5 mg/kg in dogs but only 0.1 mg/kg in horses; a dog dose given to a horse is a massive overdose
• Wash out 5–7 days when switching from another NSAID or a steroid to protect the GI mucosa
• Equioxx and Previcox are the same molecule — do not stack them

Mechanism of action

Coxib-class NSAID. Selectively inhibits the inducible cyclo-oxygenase-2 (COX-2) isoenzyme that generates the prostaglandins (chiefly PGE2) driving inflammation, pain and fever, while largely sparing constitutive COX-1 — which maintains gastric mucosal protection, renal perfusion and platelet aggregation. The result is anti-inflammatory and analgesic efficacy with a wider GI safety margin than non-selective NSAIDs.

Formulations and products

• Previcox 57 mg chewable tablet
• Previcox 227 mg chewable tablet
• Equioxx oral paste 8.2 mg/g (0.82 % w/w; 6.93 g syringe = 56.8 mg — Plumb’s p.525; Papich 5e p.369)
• Equioxx 20 mg/mL injection (horse)
• Previcox (Boehringer Ingelheim) — 57 mg / 227 mg, Flavoured chewable tablet
• Equioxx (Boehringer Ingelheim) — 8.2 mg/g paste; 20 mg/mL injection, Oral paste / IV injection

Storage

Store at 15–30 °C, dry. Keep flavoured Previcox chewables securely out of reach to prevent accidental overdose. Equioxx paste / injection per label.

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

• Deracoxib
• Dexamethasone
• Diclofenac
• Dimethyl Sulfoxide (DMSO)
• Flunixin Meglumine
• Grapiprant
• Isoflupredone Acetate
• Ketoprofen

Frequently asked questions