Sex hormone modulators: clomiphene: practice question

A Pharmacology question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

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Pharmacology · Sex hormone modulators: clomiphene

Sample item

A 27-year-old woman with polycystic ovary syndrome and anovulatory infertility is given clomiphene citrate. How does it induce ovulation?

AIt blocks hypothalamic oestrogen receptors, removing negative feedback and raising GnRH, FSH and LHBIt increases ovarian oestrogen synthesis by inhibiting aromataseCIt suppresses prolactin by acting on D2 receptorsDIt directly stimulates ovarian FSH receptors

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

A. It blocks hypothalamic oestrogen receptors, removing negative feedback and raising GnRH, FSH and LH

Clomiphene is a selective oestrogen receptor modulator that acts as an antagonist at the hypothalamus. The hypothalamus perceives low oestrogen, increasing GnRH pulses and therefore FSH and LH, which stimulates follicular growth. Multiple pregnancy, ovarian hyperstimulation, hot flushes and visual disturbances are adverse effects.

Option by option

A. It blocks hypothalamic oestrogen receptors, removing negative feedback and raising GnRH, FSH and LH (correct)
Correct. Blocking the feedback receptors increases gonadotropin release.
B. It increases ovarian oestrogen synthesis by inhibiting aromatase
Aromatase inhibition is the action of letrozole, which reduces oestrogen.
C. It suppresses prolactin by acting on D2 receptors
Prolactin suppression is the action of cabergoline or bromocriptine.
D. It directly stimulates ovarian FSH receptors
Direct FSH receptor stimulation is the action of injected gonadotropins, not clomiphene.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

Questions about this Pharmacology question

What is the answer to this Pharmacology question?

The best answer is A, It blocks hypothalamic oestrogen receptors, removing negative feedback and raising GnRH, FSH and LH. Clomiphene is a selective oestrogen receptor modulator that acts as an antagonist at the hypothalamus.

Why is "It increases ovarian oestrogen synthesis by inhibiting aromatase" not the answer?

Aromatase inhibition is the action of letrozole, which reduces oestrogen.

Why is "It suppresses prolactin by acting on D2 receptors" not the answer?

Prolactin suppression is the action of cabergoline or bromocriptine.

Why is "It directly stimulates ovarian FSH receptors" not the answer?

Direct FSH receptor stimulation is the action of injected gonadotropins, not clomiphene.

What concept does this question test?

It tests Sex hormone modulators: clomiphene in Pharmacology. The hypothalamus perceives low oestrogen, increasing GnRH pulses and therefore FSH and LH, which stimulates follicular growth. Multiple pregnancy, ovarian hyperstimulation, hot flushes and visual disturbances are adverse effects.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Sex hormone modulators: clomiphene?

Learn drugs as classes, then the exception in each class that an examiner would pick. Then use the flashcards and the other Pharmacology questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.