A 6-year-old boy with moderate acneiform folliculitis is prescribed a 6-week course of an antibiotic. His mother asks why the dermatologist specifically refused tetracycline and chose erythromycin instead. The reason is:

• A Tetracyclines suppress bone growth only in adolescents, not in younger children
• B Tetracyclines deposit in developing enamel and dentin of unerupted teeth, causing permanent yellow-brown discoloration in children under 8 years ✓
• C Erythromycin has superior activity against Cutibacterium acnes
• D Tetracyclines cause fatal hepatotoxicity in children below 12 years

Explanation

Tetracyclines chelate calcium and deposit in calcifying tissues. In children younger than eight years they stain the enamel and dentin of developing teeth permanently and can depress bone growth, so they are avoided in this age group, in pregnancy and in lactation. The staining affects unerupted teeth, which is why short maternal courses still matter. Hepatotoxicity is a feature of very high doses, not a routine paediatric hazard.

Reference: Katzung Basic and Clinical Pharmacology, 15th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.