What it's for (Indications)
- Ketorolac, a nonsteroidal anti-inflammatory drug (NSAID), is primarily indicated for the short-term (up to 5 days) management of moderately severe acute pain that requires analgesia at the opioid level.
- It is often utilized in the post-operative setting to reduce the need for opioid analgesics, thereby minimizing opioid-related side effects.
- Its potent analgesic properties make it suitable for acute pain conditions such as musculoskeletal injuries, post-surgical pain, and renal colic.
- It is crucial to emphasize that ketorolac is not indicated for chronic pain conditions or for use beyond the recommended short-term duration due to its significant risk profile, particularly concerning gastrointestinal, renal, and cardiovascular adverse events.
- The decision to initiate ketorolac therapy should involve careful consideration of the patient's overall health status and concurrent medications.
Dosage Information
| Type | Guideline |
|---|---|
| Standard | The dosage of ketorolac must be carefully individualized and should not exceed the recommended duration of 5 days for all routes of administration combined. For adults under 65 years and weighing at least 50 kg, the typical intravenous (IV) or intramuscular (IM) initial dose is 30 mg, followed by 15-30 mg every 6 hours, not exceeding 120 mg/day. For patients 65 years or older, those weighing less than 50 kg, or those with moderately impaired renal function, the recommended single dose for IV/IM administration is 15 mg, with a maximum daily dose of 60 mg. Oral ketorolac, often used as a continuation therapy after IV/IM administration, is typically 10 mg every 4-6 hours, not exceeding 40 mg/day. It is imperative to use the lowest effective dose for the shortest possible duration to minimize the risk of serious adverse effects. Dose adjustments are critical in patients with impaired renal function to prevent accumulation and toxicity. |
Safety & Warnings
Common Side Effects
- Ketorolac, like other NSAIDs, can cause a range of side effects, some of which can be severe.
- Common side effects include gastrointestinal disturbances such as nausea, dyspepsia, abdominal pain, diarrhea, and constipation.
- Central nervous system effects may include headache, dizziness, drowsiness, and somnolence.
- Renal adverse effects, such as elevated creatinine or acute renal failure, are a significant concern, especially in dehydrated or elderly patients.
- Cardiovascular effects can include hypertension, edema, and fluid retention.
- Less common but serious side effects include gastrointestinal bleeding, ulceration, or perforation; cardiovascular thrombotic events like myocardial infarction or stroke; severe hepatic dysfunction; and hypersensitivity reactions, including anaphylaxis, bronchospasm, and rash.
- Hematologic effects such as prolonged bleeding time or inhibition of platelet aggregation are also possible.
- Patients should be monitored closely for any signs of these serious adverse reactions during treatment.
Serious Warnings
- Black Box Warning: **WARNING: RISK OF GASTROINTESTINAL TOXICITY, CARDIOVASCULAR THROMBOTIC EVENTS, RENAL TOXICITY, AND BLEEDING** **Gastrointestinal (GI) Risk:** Ketorolac can cause serious GI adverse events including inflammation, bleeding, ulceration, and perforation of the stomach or intestines, which can be fatal. These events can occur at any time during use and without warning symptoms. Elderly patients and those with a history of peptic ulcer disease and/or GI bleeding are at greater risk for serious GI events. The duration of ketorolac therapy should not exceed 5 days for all routes of administration combined. **Cardiovascular (CV) Thrombotic Events:** Nonsteroidal anti-inflammatory drugs (NSAIDs) cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal. This risk may increase with duration of use. Patients with cardiovascular disease or risk factors for cardiovascular disease may be at greater risk. Ketorolac is contraindicated for the treatment of peri-operative pain in the setting of coronary artery bypass graft (CABG) surgery. **Renal Toxicity:** Ketorolac is contraindicated in patients with advanced renal impairment and in patients at risk for renal failure due to volume depletion. It can cause acute renal failure, especially in dehydrated patients or those with pre-existing renal disease. **Bleeding Risk:** Ketorolac inhibits platelet function and can cause dose-dependent prolongation of bleeding time. It is contraindicated in patients with suspected or confirmed cerebrovascular bleeding, hemorrhagic diathesis, incomplete hemostasis, and those at high risk of bleeding. Concomitant use with anticoagulants (e.g., warfarin), low-dose heparin, or antiplatelet agents (e.g., aspirin) increases the risk of serious bleeding.
- Ketorolac carries significant warnings due to its potent pharmacological effects and potential for severe adverse reactions.
- Patients should be explicitly warned about the risk of gastrointestinal (GI) toxicity, including bleeding, ulceration, and perforation, which can be fatal and may occur without warning symptoms.
- Cardiovascular (CV) thrombotic events, such as myocardial infarction and stroke, are also a serious concern, especially with prolonged use or in patients with pre-existing CV risk factors.
- Ketorolac can cause renal toxicity, including acute renal failure, particularly in elderly, dehydrated, or renally impaired patients, or those with heart failure.
- Fluid retention and edema have been observed, necessitating caution in patients with hypertension or heart failure.
- Anaphylactoid reactions and severe skin reactions, although rare, can occur.
- Liver dysfunction, including elevations in liver enzymes, may also develop.
- It is contraindicated in patients with a history of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs due to the risk of cross-reactivity.
- The duration of therapy must not exceed 5 days to mitigate these risks.
How it Works (Mechanism of Action)
Ketorolac tromethamine exerts its potent analgesic, anti-inflammatory, and antipyretic effects primarily through the inhibition of prostaglandin synthesis. It achieves this by reversibly inhibiting cyclooxygenase (COX) enzymes, specifically both COX-1 and COX-2 isoforms, though it is considered a non-selective NSAID. Inhibition of COX-1 reduces the production of prostaglandins that protect the gastric mucosa, maintain renal blood flow, and support platelet aggregation, explaining many of its gastrointestinal, renal, and bleeding-related side effects. Inhibition of COX-2 reduces the production of prostaglandins involved in inflammation and pain signaling pathways. By decreasing prostaglandin levels at the site of tissue injury and in the central nervous system, ketorolac effectively diminishes the sensation of pain and reduces inflammatory responses. Unlike opioid analgesics, ketorolac does not bind to opioid receptors, nor does it cause respiratory depression, physical dependence, or tolerance.