Ibuprofen is one of the most commonly used medicines in the world. Millions of people take it every day to treat headaches, muscle pain, fever, arthritis, back pain, and many other common health problems.
Because it is sold in supermarkets and pharmacies without a prescription in many countries, many people think of it as a very safe drug.
However, scientists are continuing to learn more about how ibuprofen affects the body, and new research suggests its impact on the liver may be more serious and more complicated than previously understood.
Researchers from the University of California, Davis recently carried out a study that examined how ibuprofen changes the liver at a deep biological level. Their findings suggest that the medicine may affect many important liver functions and that men and women could respond to the drug in very different ways.
Ibuprofen belongs to a group of medicines called nonsteroidal anti-inflammatory drugs, often shortened to NSAIDs. These drugs work by reducing inflammation, pain, and fever in the body.
Other common NSAIDs include aspirin and naproxen. Although these medicines are widely used, doctors have long known that they can sometimes cause side effects, especially when taken too often or in high doses.
In recent years, researchers have warned that long-term or heavy use of NSAIDs may increase the risk of stomach bleeding, kidney damage, heart attacks, and strokes. Now scientists are paying more attention to another important organ that may also be affected: the liver.
The liver is one of the hardest-working organs in the body. It helps remove toxins, process nutrients, store energy, break down medicines, and support digestion. Every medicine that enters the body passes through the liver in some way.
Because of this, the liver can sometimes become stressed or damaged by drugs, especially if they are used regularly.
In the new study, scientists gave mice a moderate amount of ibuprofen every day for one week. The dose was roughly equal to a human adult taking about 400 milligrams daily, which is a common amount used for pain relief.
After the treatment period, the researchers carefully studied the liver cells of the mice using advanced laboratory technology called mass spectrometry. This method allows scientists to examine tiny chemical changes inside cells in great detail.
The researchers discovered major changes inside the livers of the mice, especially in males. In male mice, ibuprofen changed at least 34 important biological pathways. These pathways control many critical functions inside the body, including the processing of amino acids, hormones, and vitamins.
One of the most concerning findings involved hydrogen peroxide. The researchers found higher levels of this chemical in the liver after ibuprofen exposure.
Hydrogen peroxide is a reactive substance that can damage proteins and place stress on cells. When cells experience this kind of stress over long periods, it may contribute to liver injury or other health problems.
The study also revealed something that surprised the researchers even more: male and female mice often reacted very differently to the drug.
In some cases, the same liver systems changed in opposite ways depending on whether the mouse was male or female. One example involved the proteasome, a system inside cells that removes damaged or unwanted proteins.
The proteasome is very important because it helps keep cells healthy and functioning properly. Researchers found that ibuprofen affected this system differently in males and females, suggesting that men and women may process or respond to the drug differently.
Scientists say this discovery could be very important for medicine in the future. For many years, researchers have suspected that sex differences may influence how drugs work in the body, but these differences are not always fully studied during drug research.
This study adds more evidence that men and women may not always experience the same effects or risks from common medicines.
Another important discovery from the study involved how the liver processes other medications. Researchers found evidence suggesting that ibuprofen may slow down how quickly the liver breaks down certain drugs in male mice.
If this also happens in humans, it could mean that some medicines remain in the body longer than expected when taken together with ibuprofen.
This could increase the risk of side effects or dangerous drug interactions. The finding is especially important because many people who use ibuprofen are also taking other prescription medications at the same time. Older adults may face an even greater risk because they are more likely to use several medicines together.
The researchers say this is the first time such an effect has been clearly reported in this way. While more studies are needed to confirm whether the same changes happen in humans, the findings raise important questions about how safely ibuprofen is being used by the public.
The scientists are not saying that people should completely avoid ibuprofen. For many patients, the medicine remains very useful and effective when taken correctly and for short periods of time. However, the researchers do warn against overusing it, especially for minor aches and pains that may not truly require medication.
Doctors also say people should carefully follow dosage instructions and avoid taking more than recommended. People who already have liver disease, kidney problems, heart conditions, or who take several medications should be especially cautious and speak with a healthcare professional before using ibuprofen regularly.
The study also highlights the growing importance of personalized medicine. Scientists hope that in the future, treatments may be better adjusted to a person’s sex, genetics, age, and overall health. Understanding how different people respond to the same drug may help doctors improve safety and reduce harmful side effects.
The research was led by Professor Aldrin Gomes from the University of California, Davis, and the findings were published in the scientific journal Scientific Reports.
As scientists continue studying common medicines more carefully, this research serves as an important reminder that even everyday painkillers can have complex effects inside the body. Medicines that seem simple and familiar may still carry risks, especially when used often or without proper medical advice.
If you care about liver health, please read studies about simple habit that could give you a healthy liver, and common diabetes drug that may reverse liver inflammation.
For more information about health, please see recent studies about simple blood test that could detect your risk of fatty liver disease, and results showing this green diet may strongly lower non-alcoholic fatty liver disease.
Copyright © 2026 Knowridge Science Report. All rights reserved.
