Phototoxicity

A non-immune, dose-dependent adverse reaction occurring when a drug or its metabolites absorb UV/visible light energy and generate reactive oxygen species or other phototoxic intermediates in the skin. Distinguished from photoallergy, which is immune-mediated. ICH S10 guidelines require phototoxicity assessment for drugs that absorb light in the 290-700 nm range and distribute to skin or eyes.

Exemples

• Fluoroquinolone (ciprofloxacin, levofloxacin) phototoxicity
• Doxycycline sun sensitivity reactions
• Amiodarone blue-gray skin discoloration and photosensitivity