Like other NSAIDs, it is useful in the treatment of acute or chronic inflammatory conditions. Sulindac is a prodrug, derived from sulfinylindene, that is converted in the body to the active NSAID. More specifically, the agent is converted by liver enzymes to a sulfide that is excreted in the bile and then reabsorbed from the intestine. This is thought to help maintain constant blood levels with reduced gastrointestinal side effects. Some studies have shown sulindac to be relatively less irritating to the stomach than other NSAIDs except for drugs of the COX-2 inhibitor class^{[citation needed]}. The exact mechanism of its NSAID properties is unknown, but it is thought to act on enzymes COX-1 and COX-2, inhibiting prostaglandin synthesis.

Its usual dosage is 150-200 milligrams twice per day, with food. It should not be used by persons with a history of major allergic reactions (urticaria or anaphylaxis) to aspirin or other NSAIDs, and should be used with caution by persons having pre-existing peptic ulcer disease. Sulindac is much more likely than other NSAIDs to cause damage to the liver or pancreas.

Sulindac seems to have a property, independent of COX-inhibition, of reducing the growth of polyps and precancerous lesions in the colon, especially in association with familial adenomatous polyposis, and may have other anti-cancer properties.^[1][2]

Sulindac is an effective tocolytic and may be used in the treatment of preterm labor. In common with other NSAIDs, sulindac is currently being investigated for its role in the treatment of Alzheimer's disease.