Motrin (ibuprofen) can be taken every four to six hours as needed for pain or fever, with a maximum of 1,200 mg per day for over-the-counter use. That’s typically three standard 400 mg doses spaced throughout the day. The exact timing depends on whether you’re dosing for an adult, a teenager, or a child, and what you’re treating.
Dosing Schedule for Adults
For mild to moderate pain, the standard adult dose is 400 mg every four to six hours. For menstrual cramps specifically, the interval tightens to every four hours because the pain tends to respond better to more consistent dosing. In either case, you should not exceed 1,200 mg in a 24-hour period when using Motrin without a prescription.
For chronic conditions like osteoarthritis or rheumatoid arthritis, doctors sometimes prescribe higher amounts, up to 3,200 mg per day split into three or four doses. But that range is only appropriate under medical supervision, not for self-treating at home.
Motrin typically starts working within 30 to 60 minutes, and pain relief lasts about four to six hours. If you find the effects wearing off closer to the four-hour mark, it’s fine to take your next dose then rather than waiting the full six hours, as long as you stay within the daily limit. Its anti-inflammatory effects, for things like swelling or joint stiffness, take longer to build. You may not feel the full anti-inflammatory benefit for one to two weeks of regular use.
Dosing for Children
Children’s Motrin doses are based on weight, not age. The packaging includes a dosing chart, and following it closely matters because underdosing won’t control fever or pain effectively, while overdosing raises the risk of side effects. The timing is the same as adults: every six to eight hours as needed, and no more than four doses in 24 hours.
Ibuprofen should not be given to babies under 6 months old. It has not been established as safe in that age group, and the FDA has not approved its use for infants younger than 6 months. If your baby is under 6 months and has a fever or is in pain, acetaminophen (Tylenol) is the safer choice, but check with your pediatrician on dosing.
How Many Days in a Row Is Safe
Even if you’re staying within the daily dose limits, duration matters. For pain, you shouldn’t take Motrin for more than 10 consecutive days. For fever, the limit is three consecutive days. If you still need it beyond those windows, something else may be going on that needs medical attention rather than more ibuprofen.
Alternating Motrin With Tylenol
If Motrin alone isn’t keeping pain or fever under control, you can alternate it with acetaminophen (Tylenol). The key is not to take both at the same time. Take one, then wait four to six hours before taking the other. You can continue alternating every three to four hours throughout the day. Write down what you took and when, because it’s surprisingly easy to lose track and accidentally double up.
When alternating, the daily ceilings still apply to each drug individually: no more than 1,200 mg of ibuprofen and no more than 4,000 mg of acetaminophen in 24 hours. For children under 12, the same alternating approach works, but you’ll want to confirm weight-based doses with a pediatrician. Taking either medication with a small amount of food, even just a few crackers or a banana, helps prevent stomach irritation.
If you find yourself alternating consistently for more than three days, that’s a good signal to check in with a provider.
Who Should Be Careful With Frequent Dosing
Ibuprofen is processed through the kidneys and can irritate the stomach lining, so certain people face higher risks even at normal doses. You should be more cautious if you are over 65, have high blood pressure or heart disease, have any history of kidney problems, or have had stomach ulcers or gastrointestinal bleeding.
Dehydration amplifies the kidney risk. If you’re sick with vomiting or diarrhea, or you’ve been sweating heavily without replacing fluids, ibuprofen is harder on your kidneys because blood flow to them is already reduced. One particularly risky combination involves taking ibuprofen alongside both a blood pressure medication (ACE inhibitor or ARB) and a diuretic (water pill). This “triple combination” raised the rate of acute kidney injury by 82% within the first 30 days in one large study. If you take blood pressure or heart medications, verify that regular ibuprofen use is safe for you.
Signs You’ve Taken Too Much
Ibuprofen overdose can happen gradually from exceeding the daily limit or all at once from taking too many pills. Early symptoms include nausea, vomiting, stomach pain, and severe heartburn. More serious signs include ringing in the ears, blurred vision, confusion, difficulty breathing, and little to no urine output. Seizures and loss of consciousness can occur in severe cases.
If you suspect an overdose, call 911 or the Poison Help hotline at 1-800-222-1222. Don’t wait for severe symptoms to appear before calling.