When Should You Take Acetaminophen Instead Of Ibuprofen?

Most of us have a go-to over-the-counter (OTC) medicine that we reach for first when dealing with aches and pains. And for many of us, the most-used bottle in the medicine cabinet is either acetaminophen (usually under the brand name Tylenol), or ibuprofen (aka Advil or Motrin). But are they interchangeable? Is one really just as effective as the other?

Both acetaminophen and ibuprofen are effective at reducing pain and fever. Ibuprofen also acts as an anti-inflammatory. But they belong to different classes of drugs, have different side effects, and behave differently in the body.

Acetaminophen is in the class of medicines called analgesics (pain relievers), which means that it reduces pain signals within the nervous system, instead of at the site of the pain itself (via Cleveland Clinic). Because of this, it works best for non-inflammatory types of pain, like fevers or stomach pain. But, because acetaminophen is broken down by the liver, if you have liver problems, opt for ibuprofen instead.

Ibuprofen, on the other hand, belongs to the class of medicines called non-steroidal anti-inflammatory drugs (NSAID). Because it acts as an anti-inflammatory drug as well as a pain reliever, it's effective in treating pain caused by inflammation.

Mike Martinez II, DO, a board-certified anesthesiologist and Assistant Professor at TCU and UNTHSC School of Medicine, says "While both can be used for fever and pain relief, ibuprofen should be chosen instead of acetaminophen for its anti-inflammatory properties when treating conditions such as osteoarthritis or rheumatoid" (via Insider). But, since ibuprofen is broken down by the kidneys, if you have kidney issues, acetaminophen is a safer bet.

While both Tylenol and Advil are considered generally safe to use, it's important to read labels and watch the dosage amounts carefully. Either one can result in side effects including nausea, vomiting, headache, and heartburn. Prolonged use of ibuprofen can also result in more serious complications like blood clots, heart attack, kidney damage, and stroke (via Cleveland Clinic).

Overall, acetaminophen is considered slightly safer. Santosh Sanagapalli, M.D., a gastroenterologist and physician in internal medicine at St Vincent's Hospital in Sydney, Australia, notes, "Because of its safety, acetaminophen should be the first-line painkiller of choice for most people with mild to moderate pain. Ibuprofen should be reserved for symptoms not responding adequately to acetaminophen."