[Column] How to choose a painkiller

When choosing a painkiller, you essentially have two main types. One option is nonsteroidal anti-inflammatory drugs (NSAIDs), and the other is fever reducers. Common NSAIDs include ibuprofen (Advil, Brufen) and naproxen (Tak-Sen). Meanwhile, acetaminophen (Tylenol) stands as the most frequently used fever reducer. Acetaminophen has a long history, seeing its initial use in Europe in 1893, though its precise mechanism of action remains uncertain. The primary theory suggests it alleviates pain by inhibiting prostaglandin synthase, an enzyme responsible for pain production within the central nervous system. However, acetaminophen has minimal impact on prostaglandin synthesis across the entire body, which explains why it doesn't reduce inflammation.

NSAIDs, on the other hand, inhibit enzymes known as COX-1 and COX-2, reducing the production of prostaglandins, which are chemicals responsible for causing inflammation, pain, and swelling. Despite their name, these medications also possess a fever-reducing effect. However, they also inhibit COX-1, crucial for protecting the gastrointestinal mucosa, which can result in side effects like stomach upset and stomach ulcers. Consequently, it is recommended to take NSAIDs after a meal rather than on an empty stomach.

Knowing that these two drug types work differently can help you decide which one to choose depending on the situation. NSAIDs are effective in relieving pain related to inflammation. This holds true whether the pain is localized, as with migraines, toothaches, and muscle pain, or systemic, as in generalized body aches and arthritis. Menstrual cramps are also an inflammatory pain caused by prostaglandins produced by the uterine lining, so NSAIDs are particularly effective. If the painful area is red, hot, or swollen, it may be inflamed, which is a good reason to use an NSAID. All NSAIDs basically work in a similar way, so you can choose the one that works best for you. However, there are differences in their duration of action. Naproxen has a longer duration of action than other NSAIDs, lasting about 12 hours, while ibuprofen works for four to six hours.

Acetaminophen proves most effective for alleviating mild pain not associated with inflammation. It can provide relief for mild arthritis pain, tension headaches, muscle aches, and symptoms of the common cold. However, it is less effective for pain primarily driven by inflammation, such as migraines or menstrual cramps. In contrast to NSAIDs, acetaminophen does not alleviate inflammation-induced symptoms like skin redness or swelling.

Awareness of potential side effects and hypersensitivity reactions is also crucial. Overuse or prolonged use of NSAIDs can increase the risk of gastrointestinal upset, kidney damage, and cardiovascular disease. Individuals who are pregnant or have a chronic medical condition should consult their doctor or pharmacist prior to taking them. Acetaminophen generally presents with relatively few adverse reactions, but excessive intake can strain the liver. This holds particularly true for individuals with liver disease or those who consume alcohol frequently.

Jeong Jae-hoon is a food writer and pharmacist. He covers a variety of subjects, including trends in food, wellness, and medications. This column was originally published in Korean in Joongang Ilbo on June 5, 2025. – Ed.