For most adults, 200 to 400 mg of ibuprofen is the right dose for a headache. That’s one to two standard over-the-counter tablets (each tablet is typically 200 mg). You can repeat the dose every four to six hours if the pain comes back, but don’t exceed 1,200 mg in a 24-hour period when self-treating without a doctor’s guidance.
Why 400 mg Works Better Than 200 mg
Both 200 mg and 400 mg doses are effective for headaches, but 400 mg consistently performs better. In pooled data from six randomized controlled trials reviewed by the World Health Organization, 400 mg produced better pain relief than 200 mg when compared against placebo. That said, head-to-head comparisons between the two doses didn’t show a statistically significant difference, which means the gap narrows once you’re already taking an effective amount. For a mild headache, starting with 200 mg is reasonable. For moderate pain or a migraine, 400 mg gives you a better shot at relief.
Soluble or liquid-gel formulations tend to work faster than standard tablets because they’re absorbed more quickly. If speed matters, that’s worth considering when you’re choosing what to grab off the shelf.
How Quickly It Works
You should start feeling relief within about 30 minutes. Ibuprofen reaches its peak concentration in your bloodstream after one to two hours, so if the headache hasn’t improved meaningfully by then, that dose has done what it’s going to do. You can take another dose after four to six hours, but taking more before that window won’t help and increases the risk of side effects.
How Ibuprofen Stops a Headache
When tissue in your body is stressed or inflamed, it produces chemicals called prostaglandins that amplify pain signals. Ibuprofen blocks the enzymes responsible for making those prostaglandins. It does this quickly and reversibly, which is why the effect wears off after several hours. This same mechanism is why ibuprofen can irritate your stomach lining: the protective layer of your gut also depends on prostaglandins to maintain itself.
Take It With Food
Ibuprofen is well known for causing stomach upset, nausea, and in some cases more serious gastrointestinal problems. Taking it with a small amount of food, even just a few crackers or a glass of milk, reduces the chance of an upset stomach. An empty stomach won’t make it dangerous for occasional use, but food acts as a buffer and makes the experience more comfortable.
The Two-Day-Per-Week Rule
This is the detail most people don’t know, and it’s arguably the most important one. If you’re reaching for ibuprofen more than two to three days per week for headaches, you risk developing medication overuse headaches (sometimes called rebound headaches). The pattern is counterintuitive: the pain reliever itself starts triggering new headaches, which leads you to take more, which makes the cycle worse.
Harvard Health recommends keeping any as-needed headache medication to no more than two to three days per week, or fewer than 10 days per month. If you find yourself exceeding that, it’s a signal that something else is going on with your headaches and a different approach is needed.
For Migraines Specifically
Ibuprofen works for migraines, but with realistic expectations. It provides meaningful pain relief in about half of people who take it for an acute migraine attack. Complete relief from both pain and associated symptoms like nausea or light sensitivity happens for only a minority. The 400 mg dose is the better choice for migraines. Timing matters too: taking it at the first sign of a migraine, rather than waiting for the pain to build, significantly improves your odds.
If ibuprofen consistently falls short for your migraines, that’s useful information to bring to a doctor. Migraine-specific treatments exist that work through different pathways.
Who Should Be Cautious
Ibuprofen is safe for most adults when used occasionally, but certain situations change the calculation:
- Heart disease or stroke history. Ibuprofen can raise cardiovascular risk, especially with long-term use. The FDA label specifically warns that continuous use may increase the risk of heart attack or stroke. If you have heart disease, high blood pressure, high cholesterol, or diabetes, talk to your doctor before making ibuprofen a go-to.
- Stomach ulcers or GI bleeding. Ibuprofen increases the risk of serious gastrointestinal events. A history of ulcers or stomach bleeding is a strong reason to choose a different pain reliever.
- Kidney disease. Your kidneys process ibuprofen, and existing kidney problems can worsen with regular use.
- Pregnancy (20 weeks or later). Ibuprofen can harm the fetus and should be avoided in the second half of pregnancy unless a doctor specifically directs otherwise.
- Blood thinners or other NSAIDs. If you’re already taking anticoagulants, aspirin, naproxen, or similar medications, adding ibuprofen increases bleeding risk. The same applies to certain antidepressants (SSRIs and SNRIs).
- Adults 75 and older. The risk of side effects rises with age, and a conversation with a doctor about the safest option is worthwhile.
Dosing for Children
Children’s ibuprofen dosing is based on weight, not age, though age can be used as a backup if you don’t know your child’s weight. Ibuprofen can be given every six to eight hours as needed. It should not be given to infants under six months old, as it hasn’t been established as safe for that age group and isn’t FDA-approved for them. Children’s formulations come in liquid concentrations that differ from adult tablets, so always check the label rather than trying to split an adult dose.