Both acetaminophen and ibuprofen may work for pain and fever, but if you also have inflammation, ibuprofen is the better choice.

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Ibuprofen is in a family of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs). Ibuprofen is the most common over-the-counter (OTC) NSAID. You probably know this drug by its two common brand names Advil and Motrin. Other OTC NASIDs include aspirin and naproxen (Aleve). Side effects of ibuprofen are like the other NSAIDs and may include common, short-term side effects as well as less common long-term side effects.

Acetaminophen vs Ibuprofen

The other common OTC pain and fever reliever is acetaminophen, with the brand name Tylenol. Although acetaminophen and ibuprofen both reduce fever and pain, acetaminophen is not an NSAID, so it does not reduce inflammation. Inflammation is swelling, redness, and warmth caused by the body’s defense system, called the immune system.

Both acetaminophen and ibuprofen may work for pain and fever, but if you also have inflammation, ibuprofen is the better choice. Inflammation is your body’s response to an infection, injury, foreign body (like a splinter), or irritation from a chemical or toxin (like a bee sting). Inflammation is a sign that your immune system is active, but it can be uncomfortable because it causes swelling, pain, heat, and redness. It can also cause loss of body functions, like loss of smell if your nose is inflamed or loss of movement if a joint is inflamed.

Ibuprofen Side Effects

The most common side effect of ibuprofen and other NSAIDs is stomach and intestinal irritation that causes heartburn, nausea, gas, constipation, or a stomachache. If you take ibuprofen for a long time or at a high dose, you can have more serious and dangerous complications like developing a bleeding ulcer or kidney damage.

You may have read or heard that ibuprofen increases your risk of stroke or heart attack. This risk is not significant if you do not already have a history of heart or blood vessel (cardiovascular) disease. If you do have a history of cardiovascular disease, ask your doctor about taking ibuprofen. It may increase your risk of heart attack or stroke by about 0.1 to 0.2 percent.

Acetaminophen Side Effects

Acetaminophen side effects are less common than ibuprofen side effects, although a few people may have nausea, vomiting, or a headache. The most serious side effect of acetaminophen only occurs if you take an overdose of more than four grams or four thousand milligrams (4000 mg). This could happen if you take more than eight extra-strength Tylenol tablets at one time. At this dose Tylenol can be very toxic to your liver, and may even be life threatening. Taking high doses of Tylenol if you are also drinking alcohol can be even more dangerous because both Tylenol and alcohol can be toxic to the liver. If you have liver disease you should talk to your doctor about acetaminophen and limit the dose to 3000 mg per day.

Ibuprofen or Acetaminophen for Headache?

For pain without inflammation, like a headache, both ibuprofen and acetaminophen will work. Some studies say that ibuprofen is a little stronger. Both drugs last about the same time and can be taken every four to six hours. Pain caused by an injury or infection that causes inflammation responds better to ibuprofen. Examples would be a sprained ankle, toothache, or infection. For women, pain caused by menstrual cycles responds better to ibuprofen because it reduces menstrual cramps.

To avoid side effects, adults should not take more than 1200 mg of ibuprofen or 3000 mg of acetaminophen in a single day. Always use these medications at the lowest dose and shortest time that gives relief. Alternating ibuprofen and acetaminophen may reduce pain more than taking either one alone. New OTC pain relievers that combine both drugs are now available.