Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most commonly used drugs worldwide to treat mild-to-moderate pain and inflammation. The widespread availability of over-the-counter NSAIDs such as ibuprofen, aspirin and sodium naproxen, for example, has allowed tens of millions of individuals to minimize the pain, swelling and inflammation linked with mild moderate athletic injuries.

But a new study indicates that many people are taking more NSAIDs than they should be.

NSAIDs are strong medicines, and their actions in the body to treat one condition can cause problems in other ways, such as increased risk of heart attack, stroke, skin reactions and serious stomach and intestinal bleeding. Generally, the side effects of NSAIDs are mild, causing a possible upset stomach and/or nausea and vomiting, which can be avoided by taking with food or milk.

Long-term or extensive ingestion of NSAIDs can result in toxicity to the kidneys and to the lining of the stomach, possibly causing ulcers. People who are older than 65 years or who have existing heart, stomach, kidney, liver or intestinal disease are more likely to have problems.

Aside from the precautions, NSAIDs are generally considered safe and effective. But just how safe are these types of drugs?

According to Dr. David Kaufman of Boston University, the attitude that users can choose their own dose regardless of label directions, along with poor knowledge of dosing limits, is associated with exceeding the daily limit. And his team's research discovered that 15 percent of ibuprofen users exceed the maximum recommended dose over a one-week period.

In a new study, 1,326 people who reported taking ibuprofen in the previous month completed online medication diaries every day for one week. NSAIDs were identified by list-based prompting. Respondents, who recorded their hourly use, were not required to know their medications were NSAIDs.

Deviations from dosing directions were programmatically determined afterward. An exit survey obtained information on demographics, medical history, physical and mental health status, attitudes regarding label reading and dosing behavior, and knowledge of product label instructions.

Overall, 55 percent of participants took ibuprofen at least three days during the week, and 16 percent took it every day. In addition to ibuprofen, 37 percent of the participants reported taking at least one other NSAID during the week, most often aspirin or naproxen. Less than half of them recognized that all the products they were taking were NSAIDs.

Personal characteristics associated with exceeding the daily limit included male sex, ongoing pain, poor physical function, daily smoking, wanting to choose the dose, not starting with the lowest dose and poor knowledge of the recommended one-time and 24-hour doses. One limitation of the study — researchers only focused on recent and current ibuprofen users, which may not have reflected what doses might be typical for sporadic or new users.

For occasional use, acetaminophen is a much safer option and effective in treating pain. However, many people use NSAIDs for indications other than pain, such as flu, allergies, fever, and there is no medical base that indicates that NSAIDs or acetaminophen are of any use under these circumstances.

Kaufman suggests that educating consumers about NSAIDs and their dosing directions could reduce excess use.

“It is important to understand how many users exceed the maximum, how they do it and what characteristics are associated with over-use," he said. "This knowledge can help guide consumer interventions to promote safer use."