Ketorolac
**Ketorolac** is a highly potent non-steroidal anti-inflammatory drug (NSAID) used primarily for short-term analgesia in veterinary medicine. - **Clinical Pearl**: While ketorolac provides profound pain relief (often compared to opioids in human medicine), its use in dogs and cats is highly controversial and generally discouraged due to the availability of safer, veterinary-approved NSAIDs. - It carries a very high risk of **gastrointestinal toxicity** (ulceration and perforation) and **renal toxicity**, especially with repeated dosing. - If used in dogs, most clinicians strictly limit treatment to **less than 3 days** and strongly recommend concurrent administration of gastroprotectants like **misoprostol** (with or without sucralfate).
Mechanism: Ketorolac exerts its analgesic, anti-inflammatory, and antipyretic effects by non-selectively inhibiting **cyclooxygenase (COX-1 and COX-2)** enzymes. **Arachidonic Acid** โ **COX-1/COX-2 Inhibition** โ Decreased synthesis of **prostaglandins** and **thromboxanes**. By blocking prostaglandin production, it reduces inflammation and pain signaling. However, the profound inhibition of constitutive COX-1 also depletes protective prostaglandins in the gastric mucosa and kidneys, leading to its severe ulcerogenic and nephrotoxic side effect profile in small animals.
Dosing by species
- As an analgesic ยท 0.25 mg/kg IM q8-12h for one or two doses ยท IM ยท q8-12h ยท 1-2 doses
- Anterior uveitis and ulcerative keratitis ยท 1 drop per eye ยท topical ยท q6-24h ยท Frequency depends on the severity of inflammation.
- As an analgesic (Mice) ยท 0.7-10 mg/kg PO once daily ยท PO ยท once daily
- As an analgesic (Rats) ยท 3-5 mg/kg PO once to twice a day; 1 mg/kg IM once to twice a day ยท PO, IM ยท once to twice a day
- As an analgesic ยท 0.3-0.7 mg/kg IV , IM, SC, PO three times daily ยท IV, IM, SC, PO ยท three times daily
- As an analgesic ยท 0.5 mg/kg IV three times daily or 0.3 mg/kg PO twice daily ยท IV, PO ยท TID (IV) or BID (PO) ยท < 3 days ยท Repeated doses have considerable potential for causing GI or renal toxicity. Treated dogs should receive misoprostol.
- As an analgesic ยท 0.3-0.5 mg/kg IV , IM q8-12h for one or two doses ยท IV, IM ยท q8-12h ยท 1-2 doses
- Anterior uveitis and ulcerative keratitis ยท 1 drop per eye ยท topical ยท q6-24h ยท Frequency depends on the severity of inflammation.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Routes of administration
Contraindications
- Active GI ulcers
- History of hypersensitivity to ketorolac
- Pre-existing hematologic, renal, or hepatic disease (relative contraindication)
- Known hypersensitivity to NSAIDs
- Use with extreme caution in patients with deep or progressive corneal ulcers
Adverse effects
- Gastrointestinal ulceration and erosion
- Gastrointestinal perforation
- Renal toxicity
- Hepatic toxicity
- Platelet inhibition (increased bleeding risk)
- Local ocular irritation
- Delayed corneal epithelial healing
- Increased intraocular pressure (IOP)
- Corneal 'melting' (keratomalacia) - reported in humans, theoretical risk in animals
Drug interactions
- ACE INHIBITORS ยท Increased risk for nephrotoxicity
- ALPRAZOLAM ยท Hallucinations reported in some human patients taking with ketorolac
- AMINOGLYCOSIDES (gentamicin, amikacin, etc.) ยท Increased risk for nephrotoxicity
- ANTICOAGULANTS (heparin, LMWH, warfarin) ยท Increased risk for bleeding possible
- ASPIRIN ยท Increased likelihood of GI adverse effects (blood loss)
- BISPHOSPHONATES (alendronate, etc.) ยท May increase risk for GI ulceration
- CORTICOSTEROIDS ยท Concomitant administration with NSAIDs may significantly increase the risks for GI adverse effects
- CYCLOSPORINE ยท May increase risk for nephrotoxicity
- FLUCONAZOLE ยท May increase NSAID levels
- FLUOXETINE ยท Hallucinations reported in some human patients taking with ketorolac
- FUROSEMIDE ยท Ketorolac may reduce the saluretic and diuretic effects of furosemide
- METHOTREXATE ยท Serious toxicity has occurred when NSAIDs have been used concomitantly; use together with extreme caution
- MUSCLE RELAXANTS, NONDEPOLARIZING ยท Ketorolac may potentiate effects
Monitoring
- Analgesic and anti-inflammatory efficacy
- Gastrointestinal signs (appetite, vomiting, diarrhea, occult blood in feces)
- Renal function parameters (BUN, creatinine, urinalysis) with repeated use
- Intraocular pressure (IOP), especially in predisposed breeds
- Corneal healing via fluorescein staining
- Signs of corneal melting or worsening ulceration
Overdose
Ketorolac has a narrow margin of safety in small animals. - **Cats**: Have developed renal toxicity at doses as low as 0.7 mg/kg. - **Mice**: The oral LD50 is 200 mg/kg. - **Clinical Signs**: GI effects, including severe GI ulceration and bleeding, are highly likely in overdoses in small animals. Metabolic acidosis has been reported in humans. - **Treatment**: Consider GI emptying for large, recent overdoses. Patients must be closely monitored for GI bleeding and renal impairment. Treat aggressively with GI protectants (sucralfate) and consider giving misoprostol early.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturerโs current label.