How long does it take ibuprofen to work?

Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is available over the counter (OTC) and by prescription in higher doses. Commonly referred to by brand names Advil and Motrin, ibuprofen works by reducing hormone-like substances called prostaglandins that cause pain and inflammation in the body. After administration, you should start feeling relief from symptoms as quickly as 20-30 minutes—depending on the form of medication you take and what you’re treating. 

Ibuprofen is often taken for discomforts such as period pain, fever, rheumatoid arthritis, back pain, and migraines. The time it takes for ibuprofen to work depends on the formulation, the route of administration, and whether you’re treating pain, fever, or inflammation. Here’s what to expect.

How long does it take for ibuprofen to work? 

“After taking ibuprofen, someone should have relief or at least an easing of their pain or fever within 20 to 30 minutes,” says Barbara Bawer, MD, family medicine physician at The Ohio State University Wexner Medical Center. “It does this by decreasing prostaglandin production, chemicals that trigger pain, fever, and inflammation in the body.” If you are taking ibuprofen for conditions caused by inflammation, it can take a couple of weeks for full relief. 

How quickly ibuprofen works is also impacted by the type you are taking:

• Oral tablets: After being taken orally, ibuprofen should begin to work in 20-30 minutes. Peak blood levels occur at approximately 120 minutes. The anti-inflammatory effects can be expected to last for four to six hours, and the medication typically exits the system within a day.
• Oral suspensions: These formulations will typically start to relieve pain in approximately 20 minutes and can be expected to last for four to six hours. Peak blood levels occur within one to two hours.
• Topical patches or creams: Topical patches or creams will typically start to relieve pain in a day or two, says Dr. Bawer.

What can affect how long it takes to work?

There are a few factors that can affect how long it takes ibuprofen to work, including:

• Age: Older adults may be more sensitive to ibuprofen due to slower clearance of the drug from the body, while children under 5 generally process the drug more quickly. However, very young infants, especially premature ones, have a much slower clearance rate, which means the effects of ibuprofen may last longer in their bodies. 
• Weight: Ibuprofen may distribute more widely throughout the body of people with obesity. However, individuals with obesity typically feel ibuprofen’s effects in the same amount of time as those of average weight.
• Food: Taking ibuprofen after eating will slow the absorption rate slightly. Taking ibuprofen on an empty stomach might result in faster pain relief, but some people are more likely to experience common side effects of ibuprofen, such as nausea/vomiting, indigestion, and stomach pain, on an empty stomach. However, gastrointestinal issues may be reduced when ibuprofen is taken with food, milk, or antacids.

Always tell your pharmacist or provider all of the medications and supplements you are taking and read all the labels and pharmacy instructions before taking ibuprofen with any other medications.

What is the standard ibuprofen dosage?

Ibuprofen dosage varies depending on your age and existing medical conditions.

Adult dosages

For adults, the typical ibuprofen dose is 200 mg to 400 mg up to four times daily. However, this can vary based on treatment needs or age. For example, certain conditions such as osteoarthritis may require higher doses. 

For adults with no medical issues, the maximum dosage in 24 hours is 3,200 mg, but it may be lower if you have health problems like heart disease, stomach ulcers, or kidney disease, according to Dr. Bawer. 

When determining a course of treatment, it’s important to consider the reason for taking ibuprofen. For example, while short-term conditions such as headaches may need only a one-time pill, ibuprofen may need to be taken every four to six hours for a few days to treat something like a muscle injury, notes Dr. Bawer.

While it is highly unlikely for someone to be taking ibuprofen daily for a full year, by doing so, your risk of developing stomach ulcers and kidney disease increases; it can also worsen liver and heart disease, according to Dr. Bawer.

You should always start with the lowest possible dose for the shortest amount of time to relieve your symptoms. If chronic pain or inflammation persist after a few months of therapy, talk to your healthcare provider about exploring a different class of NSAID or gastrointestinal protection medicine such as a protein pump inhibitor.

Children’s dosages

Children older than 2 can also be given ibuprofen as a pain reliever or fever reducer, but they generally take lower doses that are often based on weight. Typically children can take 10 mg per kg of weight every six to eight hours, up to 40 mg per kg per day—but always consult with your pediatrician first.

Who should avoid taking ibuprofen?

While ibuprofen is an over-the-counter drug, there are a few factors that you should take into consideration before taking it. 

According to Dr. Bawer, you should avoid taking ibuprofen or speak with a healthcare provider if you:

• Have allergies to ibuprofen
• Have had an allergic reaction to other NSAIDs such as naproxen
• Are pregnant
• Have had recent surgery, peptic ulcer disease, or heartburn
• Are using other NSAIDs at the same time
• Are taking medications such as blood thinners, steroids, or blood pressure medications

If you have health conditions such as heart disease, kidney or liver disease, or asthma, it’s best to talk to your healthcare provider before taking ibuprofen. Ibuprofen may increase the risk of kidney problems, liver dysfunction, breathing problems, and heart attacks—especially in older adults with these conditions.

The bottom line

Knowing that ibuprofen can begin to provide relief from common pains from sprains to toothaches in as little as 20-30 minutes—depending on the delivery method—can be helpful when these ailments arise.

While ibuprofen is generally considered safe, there are several considerations to take into account, including allergies, other medications, and stomach conditions when taking this medication. If you have any questions, discuss them with your healthcare provider or pharmacist.