Duration of Ketorolac Pain Relief
Ketorolac provides pain relief for 4-6 hours, requiring dosing every 4-6 hours as needed for pain management. 1
Dosing Information and Duration of Action
- Oral ketorolac is administered at 10mg every 4-6 hours as needed for pain, with a maximum daily dose of 40mg 1
- For patients age 17-64, initial oral dose following IV/IM dosing is 20mg once, then 10mg every 4-6 hours as needed 1
- For patients age ≥65, renally impaired, or weight <50kg, dosing is 10mg once, then 10mg every 4-6 hours as needed 1
- The elimination half-life of ketorolac is approximately 4-6 hours, which corresponds to its dosing interval 2
Maximum Duration of Treatment
- The combined duration of IV/IM and oral ketorolac therapy must not exceed 5 days in adults 1
- Exceeding the 5-day limit significantly increases the risk of serious adverse effects 1, 3
- Ketorolac should be prescribed at the lowest effective dose necessary to control pain for the shortest duration possible 3
Onset of Action
- When administered intramuscularly, peak plasma levels are reached in 45-50 minutes 2, 4
- Peak analgesic effects typically occur in approximately 1-2 hours following intramuscular injection 2
- Oral ketorolac has a slower onset of action compared to parenteral forms 5
Efficacy Compared to Other Analgesics
- Oral ketorolac provides analgesia equal to or better than aspirin, acetaminophen, and comparable to acetaminophen with codeine 5
- Intramuscular ketorolac provides analgesia equivalent to commonly used doses of meperidine and morphine 5
- Ketorolac has been rated as having good efficacy (3 on a scale of 1-4) for pain management 6
Important Precautions and Limitations
- Ketorolac is contraindicated in patients with history of peptic ulcers, GI bleeding, renal failure, compromised hemostasis, or hypersensitivity to NSAIDs 1, 3
- Risk of adverse events increases with high doses, prolonged therapy (>5 days), and in vulnerable patients such as the elderly 3
- Common adverse effects include gastrointestinal upset, edema, drowsiness, and dizziness 6
- Serious adverse effects include GI bleeding/perforation, platelet inhibition with altered hemostasis, and renal impairment 1, 3
Clinical Application
- Ketorolac is often used as part of multimodal pain management approaches, frequently combined with acetaminophen 6
- It can be used as a rescue medication for breakthrough pain when other analgesics are insufficient 6
- Ketorolac may be most useful as a supplement to parenteral opiates rather than as a sole agent for severe pain 5
- When combined with opioids, ketorolac exhibits marked opioid-sparing effects, allowing for lower opioid dosages 7