Ans. D. AceclofenacRef: Fitzpatrick's Color Atlas and Synopsis of Clinical Dermatology, 7th/ed p498-99Explanation# Findings given in question are suggestive of 'fixed drug eruptions (FDE)'.# Among the given options ofloxacin, doxycycline and azithromycin are prescription only drugs hence most probably the answer is aceclofenac.# If in question 'over the counter' has not been mentioned then the answer will be doxycycline.# A FDE is an adverse cutaneous reaction to an ingested drug, characterized by the formation of a solitary (but at times multiple) erythematous patch or plaque.# If the patient is rechallenged with the offending drug, the FDE occurs repeatedly at the identical skin site (i.e., fixed) within hours of ingestion.# Usually asymptomatic. May be pruritic, painful, or burning.# Time to onset oflesion(s): Occur from 30 min to 8 h after ingestion of drug in previously sensitized individual.# Duration oflesion(s): Lesions persist if drug is continued. Resolve days to few weeks after drug is discontinued.* Tetracyclines (tetracycline, doxycycline, minocycline)* Sulfonamides, other sulfa drugs* Metronidazole, nystatin, salicylates, NSAIDs, phenylbutazone, phenacetin* Barbiturates* Oral contraceptives* Quinine (including quinine in tonic water), quinidine* Phenolphthalein* Food coloring (yellow): in food or medications