Indometacin

Indometacin, also known as indomethacin, is a nonsteroidal anti-inflammatory drug (NSAID) commonly used as a prescription medication to reduce fever, pain, stiffness, and swelling from inflammation. It works by inhibiting the production of prostaglandins, endogenous signaling molecules known to cause these symptoms. It does this by inhibiting cyclooxygenase, an enzyme that catalyzes the production of prostaglandins.

It was patented in 1961 and approved for medical use in 1963. It is on the World Health Organization's List of Essential Medicines. In 2023, it was the 287th most commonly prescribed medication in the United States, with more than 500,000 prescriptions.

Medical uses

As an NSAID, indometacin is an analgesic, anti-inflammatory, and antipyretic. Clinical indications for indometacin include:

Joint diseases

rheumatoid arthritis

ankylosing spondylitis

osteoarthritis

gouty arthritis

acute painful shoulder bursitis or tendinitis

Headaches

Trigeminal autonomic cephalgias

Paroxysmal hemicranias

Chronic paroxysmal hemicrania

Episodic paroxysmal hemicrania

Hemicrania continua

Valsalva-induced headaches

Primary cough headache

Primary exertional headache

Primary headache associated with sexual activity (preorgasmic and orgasmic)

Primary stabbing headache (jabs and jolts syndrome)

Hypnic headache

Others

Patent ductus arteriosus

Contraindications

Concurrent peptic ulcer, or history of ulcer disease

Allergy to indometacin, aspirin, or other NSAIDs

Roux-en-Y gastric bypass and gastric sleeve patients

Patients with nasal polyps reacting with an angioedema to other NSAIDs

Children under 2 years of age (with the exception of neonates with patent ductus arteriosus)

Severe pre-existing renal and liver damage

Caution: pre-existing bone marrow damage (frequent blood cell counts are indicated)

Caution: bleeding tendencies of unknown origin (indometacin inhibits platelet aggregation)

Caution: Parkinson's disease, epilepsy, psychotic disorders (indometacin may worsen these conditions)

Concurrent with potassium sparing diuretics

Patients who have a patent ductus arteriosus dependent heart defect (such as transposition of the great vessels)

Significant hypertension (high blood pressure)

Concomitant administration of lithium salts (such as lithium carbonate)

Adverse effects

In general, the adverse effects of indometacin are similar to those of all other NSAIDs. For instance, indometacin inhibits both cyclooxygenase-1 and cyclooxygenase-2, which then inhibits the production of prostaglandins in the stomach and intestines responsible for maintaining the mucous lining of the gastrointestinal tract. Indometacin, therefore, like other non-selective COX inhibitors, can cause peptic ulcers.