Rosacea: sub-antimicrobial doxycycline: practice question

A Dermatology 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.

Try it

Dermatology · Rosacea: sub-antimicrobial doxycycline

Sample item

A patient with papulopustular rosacea is prescribed doxycycline 40 mg modified-release daily. Why is this dose used?

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

The answer and the reasoning

A. It has anti-inflammatory action without antibacterial effect at this dose

Doxycycline 40 mg modified-release is a sub-antimicrobial dose that reduces inflammation and matrix metalloproteinase activity in rosacea without selecting for antibiotic resistance. Topical ivermectin or metronidazole are alternatives. Regular dose doxycycline is used for acne and other infections.

Option by option

  • A. It has anti-inflammatory action without antibacterial effect at this dose (correct)

    Correct. The low dose is anti-inflammatory rather than antibacterial.

  • B. It is a strong bactericidal dose against Demodex

    It does not act as a bactericidal dose.

  • C. It acts as a retinoid

    Doxycycline is not a retinoid.

  • D. It is a photosensitiser

    Photosensitivity is a risk at higher doses, not the purpose.

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.

More Dermatology questions

Questions about this Dermatology question

What is the answer to this Dermatology question?

The best answer is A, It has anti-inflammatory action without antibacterial effect at this dose. Doxycycline 40 mg modified-release is a sub-antimicrobial dose that reduces inflammation and matrix metalloproteinase activity in rosacea without selecting for antibiotic resistance.

Why is "It is a strong bactericidal dose against Demodex" not the answer?

It does not act as a bactericidal dose.

Why is "It acts as a retinoid" not the answer?

Doxycycline is not a retinoid.

Why is "It is a photosensitiser" not the answer?

Photosensitivity is a risk at higher doses, not the purpose.

What concept does this question test?

It tests Rosacea: sub-antimicrobial doxycycline in Dermatology. Topical ivermectin or metronidazole are alternatives. Regular dose doxycycline is used for acne and other infections.

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 Rosacea: sub-antimicrobial doxycycline?

Learn each condition by its primary lesion, site and signature sign. Then use the flashcards and the other Dermatology 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.