Could a common painkiller help reduce cancer risk?

Dipa Kamdar, Ahmed Elbediwy and Nadine Wehida

Ibuprofen is one of the most widely used pain relievers in the United States, commonly taken for headaches, muscle aches and menstrual pain. New research suggests that this familiar medication may have effects that go beyond pain relief, and scientists are now exploring whether it could also help lower the risk of certain cancers.

As research increasingly highlights the role of inflammation in cancer development, ibuprofen has drawn growing attention. Its long-standing use as an anti-inflammatory drug has prompted interest in whether a common over-the-counter medicine could offer unexpected protection against disease.

How ibuprofen works

Ibuprofen belongs to a class of medicines known as non-steroidal anti-inflammatory drugs (NSAIDs). The link between NSAIDs and cancer prevention is not new. As early as 1983, clinical evidence showed that sulindac - an older prescription NSAID similar to ibuprofen - was associated with a reduced incidence of colon cancer in certain patients.

Since then, researchers have been investigating whether these drugs could help prevent or slow the progression of other cancers.

NSAIDs work by blocking enzymes called cyclooxygenases (COX). There are two main types. COX-1 helps protect the stomach lining, supports kidney function and plays a role in blood clotting. COX-2, by contrast, drives inflammation.

Most NSAIDs, including ibuprofen, inhibit both enzymes. This is why doctors recommend taking them with food rather than on an empty stomach.

Ibuprofen and endometrial cancer

A 2025 study found that ibuprofen may lower the risk of endometrial cancer, the most common type of womb cancer. It begins in the lining of the uterus (the endometrium) and mainly affects women after menopause.

One of the most significant preventable risk factors for endometrial cancer is being overweight or obese, as excess body fat increases levels of oestrogen – a hormone that can stimulate cancer cell growth.

Other risk factors include older age, hormone replacement therapy (particularly oestrogen-only HRT), diabetes and polycystic ovary syndrome. Early onset of menstruation, late menopause or not having children can also increase risk. Symptoms may include abnormal vaginal bleeding, pelvic pain and discomfort during sex.

In the Prostate, Lung, Colorectal and Ovarian (PLCO) study, data from more than 42 000 women aged 55 to 74 were analysed over 12 years. Women who reported taking at least 30 ibuprofen tablets per month had a 25% lower risk of developing endometrial cancer compared to those who took fewer than four tablets a month. The protective effect appeared strongest among women with heart disease.

Interestingly, aspirin – another widely used NSAID – did not show the same association with reduced risk in this or other studies. That said, aspirin has been shown to help prevent bowel cancer from returning.

Other NSAIDs, such as naproxen, have also been studied for their potential role in preventing colon, bladder and breast cancers. Their effectiveness appears to depend on the type of cancer, genetic factors and underlying health conditions.

Ibuprofen’s broader potential

Evidence suggests that ibuprofen’s possible benefits may extend beyond endometrial cancer. Studies have linked its use to a lower risk of bowel, breast, lung and prostate cancers.

For example, people who previously had bowel cancer and took ibuprofen were less likely to experience a recurrence. The drug has also been shown to inhibit colon cancer growth and survival, and some evidence suggests it may offer protection against lung cancer in smokers.

Inflammation is a hallmark of cancer, and ibuprofen is fundamentally anti-inflammatory. By blocking COX-2 enzyme activity, the drug reduces the production of prostaglandins – chemical messengers that drive inflammation and cell growth, including the growth of cancer cells. Lower prostaglandin levels may help slow or stop tumour development.

However, this is only part of the picture. Ibuprofen also appears to influence cancer-related genes such as HIF-1α, NFκB and STAT3, which help tumour cells survive in low-oxygen conditions and resist treatment.

By reducing the activity of these genes, ibuprofen may make cancer cells more vulnerable. It can also alter how DNA is packaged inside cells, potentially increasing cancer cells’ sensitivity to chemotherapy.

A word of caution

Not all research points in the same direction. One study involving 7 751 patients found that taking aspirin after an endometrial cancer diagnosis was linked to higher mortality, particularly among those who had used aspirin before diagnosis. Other NSAIDs also appeared to increase the risk of cancer-related death.

By contrast, a recent review found that NSAIDs – especially aspirin – may reduce the risk of several cancers, although regular use of other NSAIDs could increase the risk of kidney cancer. These conflicting findings highlight the complexity of the relationship between inflammation, immunity and cancer.

Despite the promise, experts caution against self-medicating with ibuprofen for cancer prevention. Long-term or high-dose use of NSAIDs can cause serious side effects, including stomach ulcers, gastrointestinal bleeding and kidney damage.

Less commonly, they may increase the risk of heart problems such as heart attacks or strokes. NSAIDs can also interact with several medications, including warfarin and certain antidepressants, raising the risk of bleeding and other complications.

The idea that a common painkiller could help prevent cancer is both intriguing and provocative. If future studies confirm these findings, ibuprofen may one day form part of a broader strategy to reduce cancer risk, particularly in high-risk groups.

For now, experts agree that the safest approach remains lifestyle-based prevention: eating anti-inflammatory foods, maintaining a healthy weight and staying physically active.

Everyday medicines may still hold unexpected potential, but until the science is settled, the most reliable advice remains simple – eat well, stay active, and speak to your doctor before using any medication for prevention. – The Conversation