NSAIDs (Non-Steroidal Anti-Inflammatory Drugs)
A class of drugs that reduce pain and inflammation by inhibiting COX enzymes. Veterinary NSAIDs (carprofen, meloxicam, grapiprant) are the mainstay of chronic pain management in dogs with arthritis.
Non-steroidal anti-inflammatory drugs (NSAIDs) are the most commonly prescribed pain management medications in dogs. They reduce inflammation, pain, and fever by inhibiting cyclooxygenase (COX) enzymes — the key enzymes in prostaglandin synthesis.
Veterinary-Approved NSAIDs
Major veterinary NSAIDs (US market):
| Drug | Brand Names | Notes |
|---|---|---|
| Carprofen | Rimadyl, Novox | Oldest; most studied; hepatotoxicity risk in some dogs |
| Meloxicam | Metacam | Once-daily; flexible dosing; widely used globally |
| Deracoxib | Deramaxx | COX-2 selective; labeled for postoperative and OA pain |
| Grapiprant | Galliprant | Prostaglandin receptor antagonist (not COX inhibitor); different mechanism and GI safety profile |
| Robenacoxib | Onsior | Short-term use; rapid onset |
Mechanism
Traditional NSAIDs inhibit COX-1 and COX-2 enzymes:
- COX-1: constitutively expressed; maintains gastric mucosal integrity, renal blood flow, and platelet aggregation. Inhibition causes GI ulceration and renal side effects.
- COX-2: inducible; drives prostaglandin production at inflammation sites. The therapeutic target.
COX-2 selective agents (deracoxib, grapiprant) have fewer GI side effects than non-selective NSAIDs (aspirin) but are not risk-free.
Monitoring Requirements
Long-term NSAID use requires periodic monitoring:
- Baseline bloodwork: CBC and chemistry before initiating long-term use
- Recheck bloodwork: every 6 months during chronic therapy (monitors kidney and liver function)
- GI monitoring: watch for vomiting, diarrhea, decreased appetite, dark or bloody stools
Human NSAIDs — Never Give to Dogs
Ibuprofen (Advil, Motrin): causes severe GI ulceration and acute kidney failure in dogs at doses close to therapeutic human doses. Potentially fatal.
Naproxen (Aleve): extremely toxic to dogs; extremely narrow safety margin; single human dose causes toxicity in most dogs.
Aspirin: cause GI ulceration; not recommended when veterinary NSAIDs are available. Combining aspirin with a veterinary NSAID dramatically increases GI ulceration risk.
Acetaminophen (Tylenol): not an NSAID but similarly problematic — causes methemoglobinemia and hepatotoxicity in dogs; do not use.