Q- A 32-year-old woman presents with a complaint of severe pain during menstruation. She is prescribed indomethacin.
Which of the following is the mechanism of action of this drug to reduce her pain?
A- Interferes with the production of leukotrienes
B- Limits the production of histamine
C- Stimulates the production of prostaglandin E2
D- Inhibits the production of prostaglandin E2
E- Inhibits the production of Phospholipase A2
Answer
Indomethacin is a nonsteroidal anti-inflammatory drug (NSAID). Its primary mechanism of action is the inhibition of cyclooxygenase (COX-1 and COX-2) enzymes, which are essential for the synthesis of prostaglandins, including prostaglandin E2 (PGE2). Prostaglandin E2 contributes to uterine contractions and dysmenorrhea. By reducing PGE2 levels, indomethacin alleviates uterine cramping and associated pain.
Leukotrienes are products of the lipoxygenase pathway, not the COX pathway. Indomethacin doesn’t interfere with their production.
Histamine is released from mast cells and is not directly affected by NSAIDs.
Corticosteroids, not NSAIDs, inhibit the production of phospholipase A2.
The correct answer is D
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D