The standard adult dose of ibuprofen is 200 mg to 400 mg per dose, taken every four to six hours as needed. Most over-the-counter ibuprofen tablets come in 200 mg strength, and adults can take one or two tablets at a time depending on the level of pain or fever. The maximum you should take without a prescription is 1,200 mg in a 24-hour period.
Standard Adult Dose
For mild to moderate pain, headaches, or menstrual cramps, the recommended dose is 400 mg every four to six hours. That’s two standard OTC tablets. You don’t need to start at 400 mg, though. One 200 mg tablet is enough for many people, and it’s worth trying the lower dose first to see if it does the job.
Over-the-counter ibuprofen typically comes in 200 mg tablets or capsules. Prescription versions are available in higher strengths for conditions like arthritis, where doctors may prescribe 1,200 mg to 3,200 mg per day, split into three or four doses. That upper range is well beyond what you’d manage on your own with OTC tablets, and it requires medical supervision.
Maximum Daily Limits
If you’re buying ibuprofen off the shelf, the ceiling is 1,200 mg per day (six 200 mg tablets). Under a doctor’s direction for chronic inflammatory conditions like rheumatoid arthritis or osteoarthritis, the maximum goes up to 3,200 mg per day. The gap between those two numbers exists because higher doses carry meaningful risks to your stomach, kidneys, and cardiovascular system, risks that need professional monitoring.
Duration matters too. Don’t take ibuprofen for more than 10 consecutive days for pain or more than 3 consecutive days for fever without checking in with a provider.
Dosing for Children
Children’s doses are based on weight, not age, though age can serve as a rough guide if you don’t have a recent weight. The general rule is 5 to 10 mg per kilogram of body weight per dose, given every six to eight hours. A children’s liquid formulation makes it easier to measure precise amounts.
Ibuprofen is not recommended for infants under 6 months old because safety data for that age group is limited. For older children and teenagers, the dose gradually increases with weight until it reaches the adult dose of 400 mg.
How Quickly It Works
Standard ibuprofen tablets typically start relieving pain within 20 to 30 minutes. Peak levels in your bloodstream arrive roughly one to two hours after you take a dose, which is when you’ll feel the strongest effect. Pain relief generally lasts four to six hours per dose, which is why the dosing interval matches that window.
Taking ibuprofen with food slows absorption slightly but reduces the chance of stomach irritation. If you’re dealing with acute pain and want faster relief, taking it on a mostly empty stomach with a full glass of water will get it into your system sooner.
Why the Dose Ceiling Matters
Ibuprofen works by blocking enzymes that produce inflammation and pain signals. Those same enzymes also help protect the stomach lining and maintain blood flow to the kidneys. At higher doses or with prolonged use, that protective function gets suppressed enough to cause real problems: stomach ulcers, gastrointestinal bleeding, and reduced kidney function.
Older adults face these risks at an elevated rate. Gastrointestinal bleeding and perforation are more common in elderly patients, and the risk climbs with increasing doses. People with existing kidney problems, heart conditions, or a history of stomach ulcers should use the lowest effective dose for the shortest time possible.
The combination of ibuprofen with certain blood pressure medications and diuretics is particularly concerning for kidney health, especially in older adults. If you take medications for blood pressure or heart disease, the interaction is worth discussing with your pharmacist or doctor before reaching for ibuprofen regularly.
What Happens if You Take Too Much
Accidentally taking an extra tablet is unlikely to cause serious harm. Doses under roughly 100 mg per kilogram of body weight (about 7,000 mg for an average adult) generally produce only mild symptoms like nausea and stomach pain. Life-threatening toxicity typically doesn’t occur until ingestion reaches around 400 mg per kilogram, a massive amount far beyond what anyone would take by mistake.
That said, chronically exceeding the recommended dose, even modestly, compounds the risks to your stomach and kidneys over time. The danger with ibuprofen isn’t usually a single large dose but the habit of taking more than you need, more often than you should, for longer than is safe.