Photosensitivity and hyperpigmentation in amiodarone-treated patients: incidence, time course, and recovery.
Amiodarone (AD) induces photosensitivity in 75% of the patients treated with this drug. Phototoxic reactions can be experimentally elicited with UVA but not with UVB. The UVA-MED is significantly reduced after 12 months of treatment. The development of photosensitivity depends on the total dose of AD; 40 g is the minimal cumulative dose requirement. Under the regimens commonly used, photosensitivity can be expected after 4 months of continuous AD treatment and appears to be unrelated to the skin type. Photosensitivity gradually decreases and returns to normal between 4 and 12 months after the withdrawal of AD. AD-related hyperpigmentation develops after an average of 20 months of continuous AD treatment and a minimal total dose of 160 g AD in about 8% of the patients (mainly of skin type I). Electron microscopic examination of the sun-exposed skin of patients without AD discoloration shows pigment deposits similar to those already described in patients with AD hyperpigmentation in exposed and non-exposed skin. Light and electronmicroscopic examination of sun-exposed skin of both clinically photosensitive and non-photosensitive patients reveals perivascular inflammation even in the absence of a clinical rash. Reduplications of vascular basal laminae occur in sun-exposed skin of both patients with and without UVA photosensitivity but are absent from non-exposed skin. In one patient, followed for 33 months after drug withdrawal, massive AD-induced hyperpigmentation was found to be reversible.
Rappersberger
K
K
Department of Dermatology I, University of Vienna, Medical School, Austria.
Hönigsmann
H
H
Ortel
B
B
Tanew
A
A
Konrad
K
K
Wolff
K
K
D000638:Amiodarone / Q000009:adverse effects*; D005145:Face; D006801:Humans; D008854:Microscopy, Electron; D010787:Photosensitivity Disorders / Q000139:chemically induced* / Q000473:pathology; D010859:Pigmentation Disorders / Q000139:chemically induced* / Q000473:pathology; D011832:Radiation Injuries; D012867:Skin / Q000473:pathology / Q000648:ultrastructure; D013472:Sunlight / Q000009:adverse effects; D013997:Time Factors; D014466:Ultraviolet Rays / Q000009:adverse effects
D000638:Amiodarone