NSAIDs, short for nonsteroidal anti-inflammatory drugs, are a class of medications that reduce pain, lower fevers, and fight inflammation. The most familiar ones are ibuprofen (Advil, Motrin), naproxen (Aleve), and aspirin. But the category is broader than most people realize, spanning both drugstore staples and prescription-only options.
How NSAIDs Work in Your Body
All NSAIDs share the same core mechanism: they block an enzyme called cyclooxygenase, or COX. This enzyme is responsible for producing prostaglandins, chemical messengers that trigger inflammation, amplify pain signals, and raise your body temperature during a fever. By slowing prostaglandin production, NSAIDs tackle all three problems at once.
This is what sets NSAIDs apart from acetaminophen (Tylenol). Acetaminophen can relieve pain and reduce fever, but it only works in the central nervous system. It does not reduce inflammation anywhere else in the body, which is why it is not classified as an NSAID. If you’re dealing with a swollen joint, a sports injury, or menstrual cramps driven by inflammation, an NSAID will typically do more than acetaminophen alone.
Over-the-Counter NSAIDs
Three NSAIDs are widely available without a prescription in the United States:
- Ibuprofen (sold as Advil, Motrin). Available in 200 mg tablets for adults, with a typical OTC maximum of 1,200 mg per day.
- Naproxen sodium (sold as Aleve). Lasts longer per dose than ibuprofen, so you take it less frequently, usually every 8 to 12 hours.
- Aspirin (sold as Bayer, Bufferin, and many generics). One of the oldest NSAIDs, also used at low doses to reduce the risk of blood clots in people with cardiovascular disease.
All three are effective for headaches, muscle aches, arthritis pain, dental pain, and fever. The main practical differences come down to how long each dose lasts and how well you tolerate it.
Prescription NSAIDs
When OTC options aren’t strong enough, or when a specific condition calls for a particular drug, doctors prescribe higher-strength or specialized NSAIDs. Common prescription NSAIDs include:
- Celecoxib (Celebrex). The only selective COX-2 inhibitor currently on the U.S. market. It targets one specific form of the COX enzyme, which tends to cause fewer stomach problems than traditional NSAIDs.
- Diclofenac (Voltaren in prescription oral form). Also available as a topical gel for localized joint pain.
- Meloxicam (Mobic). Often prescribed for osteoarthritis and rheumatoid arthritis, taken once daily.
- Indomethacin (Indocin). Frequently used for gout flares and certain types of inflammatory conditions.
- Ketorolac (Toradol). A powerful, short-term NSAID typically limited to five days of use, often given after surgery.
- Piroxicam (Feldene). A long-acting option sometimes used for chronic arthritis.
Prescription-strength ibuprofen and naproxen also exist at doses higher than what you’d find on a pharmacy shelf. Naproxen, for example, can be prescribed at doses up to 1,650 mg per day for arthritis management.
Selective vs. Nonselective NSAIDs
Your body actually has two versions of the COX enzyme. COX-1 helps protect your stomach lining and supports normal kidney and platelet function. COX-2 ramps up during injury or illness and drives inflammation. Most NSAIDs block both versions, which is why they can irritate the stomach as a side effect.
Celecoxib was designed to block mainly COX-2, sparing the protective COX-1 pathway. Studies confirm it causes fewer gastrointestinal side effects, especially when combined with a stomach-protecting medication. However, it still carries cardiovascular risks similar to other NSAIDs, so it isn’t risk-free.
Stomach, Heart, and Kidney Risks
NSAIDs are safe for most people at recommended doses over short periods. The risks climb with higher doses, longer use, and certain health conditions.
Stomach and Digestive Problems
Prostaglandins help maintain the protective mucus lining of your stomach, so blocking them can leave your stomach vulnerable. Endoscopic studies show that 20 to 30 percent of regular NSAID users develop stomach ulcers, though the majority of those ulcers never cause noticeable symptoms. The more serious concern is bleeding or perforation, which occurs in roughly 2 percent of average-risk users per year and up to 10 percent per year in high-risk patients. The greatest risk for stomach complications is during the first month of use.
Cardiovascular Effects
NSAIDs can raise blood pressure and, with prolonged use, increase the risk of heart attack and stroke. This risk is more pronounced in people who already have heart disease or multiple cardiovascular risk factors. Clinical trials found that certain NSAIDs, including some that have since been pulled from the market, nearly doubled the risk of a cardiovascular event after two to three years of daily use.
Kidney Concerns
Your kidneys rely on prostaglandins to regulate blood flow. NSAIDs can reduce that blood flow, which is generally not a problem for healthy kidneys over short periods but can cause trouble for people with existing kidney disease or dehydration.
Aspirin and Children
One critical distinction within the NSAID family: aspirin should not be given to children or teenagers. Aspirin use during a viral illness like the flu or chickenpox has been linked to Reye’s syndrome, a rare but serious condition that causes swelling in the liver and brain. Ibuprofen and acetaminophen are safer alternatives for managing fever and pain in kids.
Drug Interactions to Know About
NSAIDs interact meaningfully with several common medication classes. If you take blood thinners (anticoagulants), adding an NSAID significantly raises your risk of gastrointestinal bleeding. Antidepressants in the SSRI class, such as sertraline or fluoxetine, also increase bleeding risk when combined with NSAIDs. And combining a non-aspirin NSAID with low-dose aspirin can both increase stomach problems and potentially interfere with aspirin’s blood-thinning benefit.
People taking medications for high blood pressure should also be aware that NSAIDs can partially counteract those drugs by raising blood pressure on their own.
Choosing the Right NSAID
For occasional headaches, menstrual cramps, or minor injuries, any OTC NSAID will generally work. Ibuprofen acts quickly and wears off in four to six hours, making it easy to adjust. Naproxen lasts longer, which is convenient if you don’t want to redose as often. Aspirin remains useful for mild pain but is less commonly chosen as a first-line pain reliever because of its stronger effect on blood clotting.
For chronic conditions like arthritis, prescription NSAIDs offer more options, including once-daily dosing, topical formulations that minimize whole-body exposure, and celecoxib for people at higher risk of stomach problems. The best choice depends on your specific health profile, what other medications you take, and how long you’ll need treatment.