For many people, popping a couple—or more than a couple—Tylenol or Advil is a regular routine. These popular over-the-counter pain relievers are touted as safe and effective for everything from headaches to fevers. But do you know what you’re really taking, how it works and what the risks are?

First, it’s important to understand that acetaminophen (Tylenol) is not the same as ibuprofen (Advil). “Ibuprofen is in a family of drugs known as the non-steroidal anti-inflammatory drugs (NSAIDs), which also includes the over-the-counter drugs aspirin and naproxen,” explains Dr. William Manard, a SLUCare family physician. “These drugs work by reducing inflammation throughout the body. As many forms of pain are due to inflammation, such as arthritis pain or pain due to injuries, these drugs are quite effective in reducing pain.”

Acetaminophen, in comparison, works by reducing the body's sensitivity to pain. “We believe this occurs by reducing the sensitivity to pain signals both within the nerves and within the brain,” Manard says. “It does not reduce inflammation, and therefore acts very differently for pain than ibuprofen and other NSAIDs.”

The drugs are not interchangeable and should be chosen based on the type and cause of pain. In addition, the drugs have different potential interactions with other medications and medical conditions, risk, and ways in which they are cleared from the body.

“For example, ibuprofen is great for use for arthritis pain, however, it has to be used cautiously in the elderly due to a greater risk of stomach and kidney problems,” Manard says. “Acetaminophen interacts with fewer medications and medical conditions, but it cannot be used in people with liver problems due to its potential toxicity.”

Despite both drugs’ advertising and pervasive use, they still carry inherent risks and should be treated with the same respect as other drugs, adds Chris Grass, a clinical pharmacist at SSM DePaul Health Center. “It is extremely important for consumers to read the label and follow the dosing recommendations on the package,” Grass says. “On occasion, a physician may recommend a higher dose than is on the label, but patients should never exceed the package recommended dose without advice from their physician.”

Both medications can cause stomach irritation and ulcers, kidney problems and liver damage. “Consumption of alcohol, along with acetaminophen, can result in toxicity, and in extreme cases, liver failure and death,” Grass says. “Long-term, unmonitored use of ibuprofen can cause kidney failure and high blood pressure.”

In fact, potential liver problems are the major concern for people who take these drugs over long periods of time without proper monitoring. “If you are on either of these medications long-term, the physician would need to be aware so they could order the necessary liver function tests, etc., on a regular basis,” says Rich Johnson, pharmacy manager for the SSM Rx Express Pharmacy. “If the liver function decreases enough, it would warrant the discontinuation of these medications.”

However, both drugs may be used for long periods of time under a physician’s direction. “Ibuprofen and acetaminophen have both been available for a long time,” Manard notes. “We have decades of data on their safe use, and both drugs, when used properly, are very safe.”

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