Photosensitization reaction of drugs leading to the formation of reactive o
xygen species (ROS) cause tissue injury causing damage to various cellular
macromolecules. The aim of this study was to determine the superoxide anion
(O-2(-)) generation potential of commonly used antibiotics so that due pre
caution could be exercised to minimize their photosensitizing action and ox
idative stress potential. The selected antibiotics were examined for their
ability to produce (O-2(-)) under sunlight and artificial UVA (320-400 nm)
and UVB (290-320 nm). Lincomycin, cephalothin and erythromycin generated si
gnificant amount of O-2(-). under various irradiation conditions. Superoxid
e dismutase (SOD). an enzymatic quencher of O-2(-) inhibited O-2(-) product
ion in all drugs tested. The results suggest that due precaution are necess
ary to avoid ultraviolet radiation (UVR) after the intake of photoreactive
drugs, especially in tropical and sub tropical countries.