A fixed drug eruption (FDE) leaves a residual hyperpigmented patch. The drug most commonly responsible for FDE in India is:

• A Cotrimoxazole (trimethoprim-sulfamethoxazole) ✓
• B Penicillin
• C Metformin
• D Aspirin

Explanation

Fixed drug eruption (FDE) is characterised by a recurrent, round/oval, dusky-red/violaceous plaque that recurs at exactly the same site(s) on each re-exposure to the offending drug, resolving with prominent residual hyperpigmentation. The most common causative drug in Indian studies is cotrimoxazole (trimethoprim-sulfamethoxazole), followed by tetracyclines, NSAIDs (especially oxicams), and quinine. The FDE is mediated by tissue-resident effector memory CD8+ T cells in the epidermis that reactivate locally upon systemic drug challenge. The pathomechanism (tissue-resident memory T cells) is a favoured exam topic.

Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.