Adults can take Motrin (ibuprofen) every 4 to 6 hours as needed for pain, with a standard dose of 200 to 400 mg each time. The key limits: don’t exceed 1,200 mg in 24 hours when using over-the-counter strength, and don’t use it for more than 10 consecutive days without medical guidance.
Standard Dosing for Adults
For general pain relief, the recommended adult dose is 200 to 400 mg every 4 to 6 hours. For menstrual cramps, the interval tightens slightly to every 4 hours at 400 mg, since cramping pain tends to return faster. In either case, three doses of 400 mg spread across the day (1,200 mg total) is the over-the-counter ceiling. Prescription doses can go higher, but that’s a different situation with closer medical oversight.
Each dose starts working within 30 to 60 minutes and has a half-life of about 2.5 hours, meaning half the active ingredient has left your system by then. That’s why relief fades around the 4- to 6-hour mark and another dose becomes appropriate. If you find yourself needing a dose right at the 4-hour mark every time, that’s fine occasionally, but consistently needing the maximum frequency suggests the underlying problem may need a different approach.
Dosing for Children
Children’s doses are based entirely on weight, not age. A 25-pound toddler and a 90-pound preteen need very different amounts, so checking your child’s weight before giving any dose is essential. Children’s Motrin comes in liquid (100 mg per 5 mL) and chewable tablets (100 mg each). Infant drops are more concentrated at 50 mg per 1.25 mL, so the two are not interchangeable without adjusting the volume.
As a rough guide:
- 12 to 17 lbs: 1.25 mL of infant drops or 2.5 mL of children’s liquid
- 24 to 35 lbs: 5 mL of children’s liquid or one 100 mg chewable tablet
- 48 to 59 lbs: 10 mL of children’s liquid or one adult 200 mg tablet
- 72 to 95 lbs: 15 mL of children’s liquid or 1.5 adult tablets
- 96 lbs and up: standard adult dosing (200 to 400 mg)
Do not give ibuprofen to babies under 6 months old. For children under 2 years or under 12 pounds, check with a pediatrician first. The dosing interval for children is the same as adults: every 6 to 8 hours, with no more than three doses in 24 hours unless a doctor advises otherwise.
What Happens if You Take It Too Often
Ibuprofen belongs to a class of drugs called NSAIDs, and all of them carry a black box warning about gastrointestinal risks. Frequent use can irritate the stomach lining, and in more serious cases, small erosions (ulcers) can develop. These erosions sometimes cause internal bleeding, which can happen without any warning symptoms beforehand. Stomach perforation, an actual hole in the stomach wall, is rare but possible.
Older adults and anyone with a history of stomach ulcers face higher risk from these complications. But even healthy adults aren’t immune, especially when doses climb above 1,200 mg per day. At higher prescription-level doses, the risk of stomach irritation jumps to 2 to 3 times the baseline rate.
Your kidneys are the other major concern. Taking 6 or more pills a day for 3 or more years is a recognized threshold for a condition called analgesic nephropathy, which is progressive kidney damage caused by pain relievers. You don’t need to hit that extreme to cause problems, though. Even moderate overuse over weeks or months can strain kidney function, particularly if you’re dehydrated or already have reduced kidney health.
Taking Motrin With or Without Food
You’ve probably heard you should always take ibuprofen with food. The evidence behind that advice is actually weaker than most people assume. At standard over-the-counter doses (up to 1,200 mg per day for up to a week), taking ibuprofen on an empty stomach is safe and actually provides faster pain relief. Food slows down how quickly the drug is absorbed, though the total amount absorbed stays the same.
No high-quality study has demonstrated that eating food alongside ibuprofen prevents stomach side effects at these lower doses. That said, if you’re taking higher doses or using it for more than a week, taking it with a meal is a reasonable precaution since the gastrointestinal risk profile changes meaningfully above 1,200 mg per day.
How to Space Doses Effectively
If you’re managing pain over the course of a day, spacing doses every 6 hours (roughly at breakfast, lunch, dinner, and bedtime) keeps a steadier level of relief while staying well within safe limits. Going to the minimum 4-hour interval gives you more flexibility for breakthrough pain but also pushes you closer to the daily maximum faster.
A practical approach for short-term pain: take your first dose, note the time, and wait at least 4 hours before considering another. If the pain is manageable at 5 or 6 hours, wait. Use the shortest duration and the fewest doses that handle your pain. For anything lasting beyond 10 days, the pain itself is the problem to solve, not just the symptom to cover.