Acetaminophen vs. ibuprofen: Which one to take and when?

It's not always easy knowing what to do when you or a loved one isn’t feeling well. While it’s always a good idea to consult your doctor about any over-the-counter (OTC) medications you're considering taking, many people commonly turn to acetaminophen or ibuprofen for minor aches, pains and fevers. But which one should you take and when?

Here's your guide to acetaminophen and ibuprofen, and the differences between them.

When to take acetaminophen

Acetaminophen is often used for:

• Mild to moderate fever
• Mild to moderate pain
• Headache
• Muscle ache
• Toothache

It’s not quite well understood how it works, but it’s thought to act on pathways in our central nervous system to block pain and on the heat-regulating part of our brain (the hypothalamus) to reduce fevers.

Side effects and risks of acetaminophen

The most common concern people have about acetaminophen is its effects on the liver. It’s true that if taken in excess, acetaminophen can cause liver toxicity that can be severe enough to warrant a liver transplant. But acetaminophen is quite safe when taken in appropriate amounts.

How much acetaminophen to take

When taking acetaminophen, always follow the dosing recommendations on the label or that your doctor prescribes. In general, for adults with normal liver function, you can take up to 3 g/day (1000 mg every 8 hours) without any risk to your liver.

For those with heavy alcohol use, malnutrition or low body weight, advanced age or liver disease, you can usually take up to 2 g/day without risk of liver damage. Children’s doses are based on their age and size, so you need to consult your pediatrician for more information.

The biggest thing to remember is more does not necessarily mean better. Taking more than the recommended doses does not mean it will provide more pain relief or reduce the fever more effectively. Higher than recommended doses actually have little to no benefit and come with risks to your health.

One of the other things to remember with acetaminophen is that it is commonly found in other medications, both over-the-counter (OTC) and prescription. Make sure you read your labels to ensure you’re not overdosing on acetaminophen accidentally.

For example, some cold remedies contain acetaminophen. If you’re already taking 3 g/day of acetaminophen and add cough syrup for a cold, you could unintentionally be taking higher than recommended doses of acetaminophen.

When to take ibuprofen

Ibuprofen is best taken when you have a fever or inflammation. It may be a good option when you’re experiencing things like:

• Osteoarthritis
• Sprains and strains
• Swelling
• Back pain
• Gout
• Menstrual cramps

Ibuprofen works on enzymes in our body (COX-1 and 2) that are important pathways involved in inflammation, pain and fever. It is classified in a category of medicines called non-steroidal anti-inflammatory drugs (NSAIDs), which includes other medicines that work similarly like naproxen, diclofenac and meloxicam.

Side effects and risks of ibuprofen

Ibuprofen and other NSAIDs can have serious side effects and must be taken with caution. They can increase your risk of heart attack and stroke, serious gastrointestinal bleeding from ulcers or (very rarely) perforation of your stomach and intestines.

NSAIDs can also prolong bleeding time, which can lead to significant hemorrhage, especially if someone is already taking a blood thinner. They can also cause kidney diseases like interstitial nephritis, renal papillary necrosis or even just acute kidney injury.

Because of these potentially serious problems, people who are taking blood thinners or living with health problems like heart disease or kidney disease, or have a history of gastrointestinal disease or bleeding disorders, should not take NSAIDs at all.

When taken appropriately, ibuprofen can be very helpful, and the risks can be minimized. For example, a healthy person with a fever should be able to take ibuprofen for 1-2 days without worrying about any risks.

However, you should always consult your doctor about whether ibuprofen is safe for you and for how long. Those with chronic pain or chronic health conditions like rheumatoid arthritis may require long-term use of anti-inflammatories and may need to be monitored with blood tests to ensure the NSAIDs are not causing any harm.

How much ibuprofen to take

Always follow the dosing recommendations on the label or as prescribed by your doctor. The maximum amount of ibuprofen for healthy adults is 800 milligrams per dose or 2400 mg per day (3 maximum doses). A child’s dose is based on the age and weight of the child, so consult your pediatrician about what dose is right for their needs.

Ibuprofen vs. acetaminophen for a headache

Ibuprofen and acetaminophen can both be effective for treating headaches, but they work in different ways and have different benefits and risks. Ibuprofen works by reducing inflammation in the body, which can help alleviate headache pain caused by inflammation of blood vessels or muscles. Ibuprofen also has pain-relieving and fever-reducing properties. 

Acetaminophen, on the other hand, primarily works as a pain reliever and fever reducer by blocking pain signals in the brain. It is particularly effective for headaches caused by tension or mild to moderate pain.

Ibuprofen vs. acetaminophen for fever

For fever alone, both medications are effective, but ibuprofen may offer added benefits for inflammatory conditions.

Ibuprofen vs. acetaminophen for pain

Choosing between ibuprofen and acetaminophen for pain relief depends on the type of pain and your overall health. Ibuprofen is often more effective for pain caused by inflammation, such as arthritis, muscle strains, and sprains, as well as menstrual cramps. It also helps reduce fever. 

Acetaminophen, on the other hand, is effective for general pain relief, such as headaches, toothaches, and general aches and pains. It also reduces fever and is less likely to cause stomach irritation, making it a better option for those with stomach issues.

Are Ibuprofen and acetaminophen the same thing?

The biggest difference between acetaminophen and ibuprofen is ibuprofen’s anti-inflammatory effects, which acetaminophen does not have. Therefore, pain that is caused by inflammation responds better to ibuprofen than it would to acetaminophen. 

For problems that might not be related to inflammation, such as fevers and headaches, always try acetaminophen first. It can work just as well as, if not better than ibuprofen.

If you’re experiencing pain, fever or injury, talk to your doctor about the best pain management options for you.