A child with permanently stained teeth reports to the clinic. He was most probably administered:

Teeth and bones   Tetracyclines have chelating property. Calcium-tetracycline chelate gets deposited in developing teeth and bone. Given from mid pregnancy to 5  months of extrauterine life, tetracyclines affect the deciduous teeth.  Brown discolouration, ill-formed teeth which are more susceptible to caries are produced. Tetracyclines given between 3 months and 6 years of age affect the crown of permanent anterior dentition. Repeated courses are more damaging.  Given during late pregnancy or childhood, tetracyclines can cause temporary suppression of bone growth. Doxycycline 100 mg once or twice daily is the most commonly used tetracycline. Reference: Essentials of Medical Pharmacology Eighth Edition KD TRIPATHI page no 760,786