Common Drug Eruptions: Pattern Recognition

Drug eruptions are among the most common reasons for dermatology consultation. Key patterns include: Morbilliform/Exanthematous (Most Common) Symmetric, erythematous macules and papules Common culprits: Antibiotics (amoxicillin, sulfonamides), anticonvulsants, allopurinol Onset: 7-14 days after drug initiation Urticarial Wheals and angioedema Common culprits: NSAIDs, ACE inhibitors, antibiotics Onset: Minutes to hours Fixed Drug Eruption Recurrent, well-demarcated violaceous patches at same site Common culprits: NSAIDs, sulfonamides, tetracyclines DRESS Syndrome Widespread eruption with fever, eosinophilia, organ involvement Common culprits: Anticonvulsants, allopurinol, sulfonamides Onset: 2-8 weeks SJS/TEN Mucocutaneous necrosis, target lesions, epidermal detachment Common culprits: Sulfonamides, anticonvulsants, allopurinol, NSAIDs Medical emergency requiring immediate management