Ketorolac Tromethamine — Veterinary Vademecum Drug Reference

Dosage & Administration Guidelines

Species	Route	Dose	Frequency	Duration & Clinical Notes
Dog	Oral	0.5-1 mg/kg	q12h	Duration: Up to 3-5 days Notes: Use lowest effective dose; not recommended for long-term use.
Dog	Intravenous	0.3-0.5 mg/kg	q12h	Duration: Up to 3 days Notes: For post-operative pain; monitor renal function.
Cat	Oral	0.25-0.5 mg/kg	q24h	Duration: Up to 2-3 days Notes: Use with extreme caution; risk of renal toxicity.
Cat	Intravenous	0.2-0.3 mg/kg	q24h	Duration: Up to 2 days Notes: Not recommended for routine use; consider alternative NSAIDs.
Horse	Intravenous	0.5 mg/kg	q12h	Duration: Up to 3 days Notes: Limited data; use only if other NSAIDs are unavailable.
Rabbit	Oral	Not established	Not established	Duration: Not established Notes: Not recommended due to high risk of renal toxicity.

Clinical Indications & Species Uses

General Indications

Short-term management of moderate to severe pain
Post-operative pain relief
Ocular inflammation (topical)

Dog (Canine)

Short-term management of moderate to severe pain
Post-operative pain relief
Ocular inflammation (topical use)

Cat (Feline)

Short-term management of moderate to severe pain (limited use due to safety concerns)
Post-operative pain relief (with caution)

Pharmacology & Mechanism of Action

Drug Class: Nonsteroidal Anti-inflammatory Drug (NSAID) | Pharmacological Group: Pyrrolizine carboxylic acid derivative

Mechanism of Action: Ketorolac tromethamine is a non-selective inhibitor of cyclooxygenase (COX-1 and COX-2) enzymes, thereby blocking the conversion of arachidonic acid to prostaglandins and other inflammatory mediators. This results in analgesic, anti-inflammatory, and antipyretic effects. It is a racemic mixture, with the S-enantiomer being pharmacologically active.

Pharmacodynamics: Ketorolac produces potent analgesic effects, particularly for moderate to severe pain, with anti-inflammatory activity less pronounced than its analgesic effect. It does not have significant opioid receptor activity and does not cause respiratory depression or sedation. Its effects are mediated by reduction of prostaglandin synthesis in peripheral tissues and possibly central nervous system.

⚡ Pharmacokinetics Summary

Absorption: Ketorolac is rapidly and completely absorbed after oral administration, with peak plasma concentrations occurring within 30-60 minutes. After intramuscular injection, peak concentrations are achieved in 30-60 minutes. Bioavailability is approximately 80-100% for oral and IM routes.

Distribution: Ketorolac is widely distributed in tissues, with a volume of distribution of approximately 0.1-0.3 L/kg in humans. It crosses the placenta and is distributed into milk. Protein binding is high (approximately 99%) in humans, primarily to albumin.

Metabolism: Ketorolac undergoes hepatic metabolism, primarily via conjugation with glucuronic acid and hydroxylation. The major metabolites are inactive. In animals, metabolism may vary by species.

Excretion: Ketorolac and its metabolites are primarily excreted in the urine (approximately 90%), with the remainder in feces. Renal clearance is the major route of elimination.

Half-Life: In dogs: approximately 3-4 hours; in cats: approximately 4-6 hours; in horses: approximately 1-2 hours; in humans: 5-6 hours.

Bioavailability: Oral: ~80-100%; IM: ~100%.

Protein Binding: Approximately 99% in humans; may be lower in some animal species.

Available Formulations & Strengths

Oral Tablet 10 mg (Oral)

Injectable Solution 15 mg/mL, 30 mg/mL (IV/IM)

Ophthalmic Solution 0.5% (Ophthalmic)

Contraindications & Clinical Warnings

Contraindications:

Known hypersensitivity to ketorolac or other NSAIDs
Active gastrointestinal ulceration or bleeding
Renal insufficiency or failure
Hypovolemia or dehydration
Coagulopathies or bleeding disorders
Concurrent use of other NSAIDs or corticosteroids
Pregnancy (especially late gestation) and lactation
In cats, due to high risk of renal toxicity

Warnings & Clinical Precautions:

Use with caution in animals with pre-existing renal, hepatic, or cardiac disease
Monitor renal function and hydration status during therapy
Avoid use in animals with hypotension or shock
Do not exceed recommended duration of therapy
Use lowest effective dose for shortest duration
In food animals, not approved; extra-label use prohibited
Ophthalmic use may delay corneal healing
May mask signs of infection

Adverse Effects & Reactions

Common:

Gastrointestinal upset (vomiting, diarrhea, anorexia)
Elevated liver enzymes
Renal effects (increased BUN/creatinine)

Serious / Severe:

Gastrointestinal ulceration or perforation
Acute renal failure
Hepatotoxicity
Bleeding disorders
Anaphylaxis

Rare:

Bone marrow suppression
Neurological signs (seizures, ataxia)
Ocular effects (corneal ulceration with topical use)

Key Drug Interactions

Interacting Drug / Class	Clinical Effect & Mechanism	Severity
Other NSAIDs (e.g., carprofen, meloxicam)	Increased risk of gastrointestinal ulceration and renal toxicity	High
Corticosteroids (e.g., prednisone)	Increased risk of gastrointestinal ulceration	High
Anticoagulants (e.g., warfarin, heparin)	Increased risk of bleeding	High
Diuretics (e.g., furosemide)	Reduced diuretic efficacy and increased risk of renal toxicity	Moderate
ACE inhibitors (e.g., enalapril)	Reduced antihypertensive effect and increased risk of renal impairment	Moderate
Aminoglycosides (e.g., gentamicin)	Increased risk of nephrotoxicity	Moderate

Overdose & Toxicity Management

Signs of Toxicity:

Vomiting
Diarrhea
Gastrointestinal bleeding
Renal failure
Lethargy
Seizures
Coma

Emergency Treatment Protocol: Treatment is primarily supportive. Induce emesis if recent ingestion and animal is conscious. Administer activated charcoal to reduce absorption. Provide intravenous fluids to maintain renal perfusion. Monitor renal function, liver enzymes, and coagulation parameters. Use gastroprotective agents (e.g., sucralfate, H2 antagonists, proton pump inhibitors) if gastrointestinal signs occur. In severe cases, consider hemodialysis or peritoneal dialysis.

Food Animal Withdrawal Times

Not approved for use in food animals. Extra-label use is prohibited in the United States and many other countries. No withdrawal times established.

Storage, Handling & Regulatory Information

Storage Temperature: Store at controlled room temperature 20-25°C (68-77°F), excursions permitted between 15-30°C (59-86°F).

Light Sensitivity: Light-sensitive — protect from direct exposure.

Handling & Special Conditions: Protect from light. Keep container tightly closed. Do not freeze injectable solution.

Dispensing Status: Prescription Required (Rx Only)

Approval Status: Approved for human use; not FDA-approved for veterinary use, but may be used extra-label in companion animals.

Extra-Label (Off-Label) Use: Extra-label use in food animals is prohibited by the FDA (AMDUCA) due to lack of withdrawal times and potential for human food safety concerns. In companion animals, extra-label use is permitted under veterinary supervision.

Clinical Pearls & Practice Notes

💡 Clinical Insights: Ketorolac is a potent NSAID used primarily for short-term management of moderate to severe pain in dogs and cats. Its use is limited by significant adverse effects, particularly gastrointestinal and renal toxicity. It should be reserved for cases where other NSAIDs are ineffective or contraindicated. In cats, it is rarely recommended due to high risk of renal failure. Topical ophthalmic formulations are used for ocular inflammation, but caution is advised regarding corneal healing. Always use the lowest effective dose for the shortest duration. Monitor renal function and hydration status, especially in animals with pre-existing conditions. Avoid concurrent use with other NSAIDs or corticosteroids. In horses, use is limited and not well-documented. Not for use in food animals.

References & Literature

📚 Plumb's Veterinary Drug Handbook
📚 Papich Veterinary Pharmacology and Therapeutics
📚 Compendium of Veterinary Products (CVP)