Systemic drug induced photosensitivity

Abstract

Drug-induced photosensitivity refers to the adverse cutaneous response to exogenous agents after exposure to ultraviolet radiation or visible light. It is classified into two types based on their pathogenesis: phototoxic reaction and photoallergic reaction. It is an uncommon dermatological problem and is often misdiagnosed, underdiagnosed, or underreported. This study is a literature review of the available English language literature on drug-induced photosensitivity from systemic drugs, the mechanism involved, clinical presentations, diagnosis, prevention, and management. Drugs commonly reported for inducing photosensitivity are hydrochlorothiazide, voriconazole, vemurafenib, tetracyclines (doxycycline, tetracycline), NSAIDs (ketoprofen, naproxen, piroxicam), quinolones (nalidixic acid, ciprofloxacin, lomefloxacin), chlorpromazine, and amiodarone. Phototoxic reaction results from direct cellular damage that typically presents as a sunburn like reaction. Photoallergic reaction is a delayed hypersensitivity reaction that presents as an eczematous eruption. Diagnosis is mainly based on the history of drug intake and sun exposure and the appearance of cutaneous eruption primarily affecting sun-exposed areas of the body. Phototesting, photopatch testing, and rechallenge testing can aid in the diagnosis when the relationship between drug intake and rash onset is unclear. The mainstay of management is the discontinuation of the culprit drug. Prevention includes informing patients on the risk of photosensitivity and advising on sun protection and avoidance