Indomethacin is what type of medication?

• A. Prostaglandin inhibitor
• B. Calcium channel blocker
• C. Beta agonist
• D. Antibiotic

Answer: (A)

Indomethacin is a prostaglandin synthesis inhibitor. It’s an NSAID that blocks the cyclooxygenase (COX) enzymes, which lowers the production of prostaglandins. Prostaglandins promote uterine contractions and cervical ripening, so reducing them with indomethacin helps suppress preterm labor, making it a tocolytic. It isn’t a calcium channel blocker, which works by affecting calcium flow in smooth muscle; it isn’t a beta agonist, which would stimulate adrenergic receptors; and it isn’t an antibiotic, which targets bacteria. In obstetric practice, it’s used earlier in pregnancy because of risks like ductus arteriosus closure and oligohydramnios with prolonged use.