Drug reactions: doxycycline photo-onycholysis: 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.

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Dermatology · Drug reactions: doxycycline photo-onycholysis

Sample item

A woman on doxycycline for acne notices painless separation of several nails from the distal nail bed after a holiday in the sun. What is this reaction?

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

The answer and the reasoning

B. Photo-onycholysis, a phototoxic reaction

Tetracyclines, particularly doxycycline, can cause phototoxic reactions including sunburn-like skin and photo-onycholysis. The reaction is dose-dependent and relates to UVA exposure. Management is photoprotection and stopping or changing the drug.

Option by option

  • A. Beau lines from systemic illness

    Beau lines are transverse grooves, not nail separation.

  • B. Photo-onycholysis, a phototoxic reaction (correct)

    Correct. Photo-onycholysis is a phototoxic tetracycline effect.

  • C. Allergic contact dermatitis to nail polish

    Nail polish allergy causes paronychia and eyelid dermatitis.

  • D. Fixed drug eruption

    Fixed drug eruption shows recurring plaques at one site.

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 B, Photo-onycholysis, a phototoxic reaction. Tetracyclines, particularly doxycycline, can cause phototoxic reactions including sunburn-like skin and photo-onycholysis.

Why is "Beau lines from systemic illness" not the answer?

Beau lines are transverse grooves, not nail separation.

Why is "Allergic contact dermatitis to nail polish" not the answer?

Nail polish allergy causes paronychia and eyelid dermatitis.

Why is "Fixed drug eruption" not the answer?

Fixed drug eruption shows recurring plaques at one site.

What concept does this question test?

It tests Drug reactions: doxycycline photo-onycholysis in Dermatology. The reaction is dose-dependent and relates to UVA exposure. Management is photoprotection and stopping or changing the drug.

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 Drug reactions: doxycycline photo-onycholysis?

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.