Ketorolac: what it treats, how to take it, side effects
Last updated September 3, 2026.
Ketorolac is an NSAID with the strength of an opioid-class pain reliever - and the warning list to match. Its rule is carved in stone: five days, maximum, ever. It is for the short, sharp pain after surgery, nothing longer.
What does it treat?
Short-term relief of moderately severe pain, usually after surgery. Not mild pain, not chronic pain, not longer than 5 days. The first doses come by injection in a hospital or office; the oral tablets continue the course - and all oral ketorolac stops on the fifth day after the first injection, whatever the count on the bottle says. Pain that persists past day five is a doctor conversation, not more ketorolac.
How do you take it?
A tablet every 4 to 6 hours on a schedule or as needed for pain, exactly as directed - never more of it, never more often. Do not take aspirin or other NSAIDs - ibuprofen, naproxen - alongside it. The five-day clock started at the injection, so know your date. Missed dose on a schedule: take it when you remember unless the next one is close; never double up.
Side effects to know
- Common: headache, dizziness, drowsiness, diarrhea, constipation, gas, mouth sores, and sweating.
- Serious - stop taking it and call your doctor immediately: the stomach-bleeding pattern - stomach pain, heartburn, vomit that is bloody or looks like coffee grounds, blood in the stool, or black tarry stools; the kidney pattern - swelling of hands, arms, feet, ankles, or legs, unexplained weight gain, confusion, or seizures; the liver pattern - nausea, loss of appetite, upper-right stomach pain, yellowing of skin or eyes, flu-like symptoms, excessive tiredness, or pale skin; the heart-and-stroke pattern - chest pain, shortness of breath, weakness on one side, or slurred speech (get emergency help); cloudy, discolored, or bloody urine; unexplained weight gain with abdominal swelling; fever and blisters; and the allergic pattern - rash, hives, itching, swelling of the eyes, face, throat, or tongue, difficulty breathing or swallowing, or hoarseness.
Who should not take it?
Anyone with a recent heart attack (unless their doctor directs it), anyone right before or after coronary bypass surgery, and anyone allergic to ketorolac, aspirin, or other NSAIDs - especially with asthma plus nasal polyps. The risk flags: heart disease, stroke or ministroke history, smoking, high cholesterol, high blood pressure, bleeding or clotting problems, diabetes, ulcers or stomach bleeding history, kidney or liver disease, dehydration, and older age. The interaction list is long: blood thinners, aspirin, oral steroids, SSRIs and SNRIs, ACE inhibitors, and diuretics all raise the stakes. Heavy alcohol use compounds the bleeding risk. If you become pregnant, call your doctor.
When is it an emergency?
Chest pain, one-sided weakness, slurred speech, bloody or coffee-ground vomit, black stools, or throat swelling is a 911 call. For an overdose, call Poison Control at 1-800-222-1222. Pymander's escalation routing is built and tested specifically for this class of decision; see the safety architecture working paper.
What a Pymander AI doctor consult looks like
Illustrative example, not a real member's messages.
Common questions
Why is ketorolac limited to 5 days?
Because its risks climb steeply with time - stomach and intestinal bleeding, kidney failure, heart attack, stroke - and MedlinePlus caps it plainly: not longer than 5 days, not for mild pain, not for chronic conditions. The five days run from the first injection, not the first tablet. Pain past day five is a conversation about the next plan, never a ketorolac extension.
If it is just an NSAID, why is it treated so seriously?
Strength plus route: ketorolac hits like an opioid-class analgesic, which is why it earns its place after surgery - and the NSAID class warnings land harder at that strength. The label stacks them all: heart attack and stroke risk without warning, ulcers and bleeding and holes in the stomach or intestine without warning symptoms, and kidney failure. Five days of a strong drug is manageable; open-ended use is where the damage happens.
Why can't I take ibuprofen in between ketorolac doses?
Same class, stacked risk: aspirin and other NSAIDs - ibuprofen, naproxen - are explicitly out while you take ketorolac. Two NSAIDs do not add pain relief; they add bleeding and kidney risk. Blood thinners, oral steroids, and SSRI or SNRI antidepressants raise the bleeding risk too - your prescriber has the full list, and this is why they asked for it.
Why did the nurse ask about my kidneys and my water intake?
Ketorolac can cause kidney failure, and dehydration invites it - the label calls out severe vomiting, diarrhea, and dehydration as risk flags, plus ACE inhibitors and diuretics as compounding medications. The watch signs: swelling of hands, feet, ankles, or legs, unexplained weight gain, confusion. In the days after surgery, drinking enough is genuinely part of the prescription.
Why did my doctor ask if I had ever had stomach ulcers?
Because ketorolac can cause ulcers, bleeding, or holes in the stomach or intestine - at any time during treatment, without warning symptoms, per the label - and a past ulcer or stomach bleed multiplies that risk, as do age, poor health, and heavy alcohol use. The symptom set that stops everything: stomach pain, heartburn, bloody or coffee-ground vomit, blood in stool, or black tarry stools.
What happens if I miss a dose of ketorolac?
If you take it on a schedule: take it when you remember, unless it is almost time for the next one - then skip it and never double up. Doubling stacks the kidney and stomach risk. And keep the date math honest: the missed-dose question never extends the course - day five is day five.