The spectrum of cutaneous reactions associated with calcium antagonists: a review of the literature and the possible etiopathogenic mechanisms.
Calcium antagonists (CAs) or calcium-channel blockers, are a common group of antihypertensive medications. These drugs have the property of blocking the calcium channels of the vascular and cardiac smooth-muscle fibers. They have been associated with cutaneous reactions ranging from exanthems to severe adverse events. The frequency of these reactions may be as high as 48 percent. The most common are ankle or pedal edema (up to 30 %), gingival hyperplasia (up to 21 %), and flushing (up to 10 %). Less common are facial or truncal telangiectasia, photosensitivity reactions, new-onset psoriasis (as well as exacerbation of it), purpuric exanthems, pemphigoid manifestations, subacute cutaneous lupus erythematosus, gynecomastia, erythromelalgia, and oral ulcers. Particular adverse manifestations relate to drug potency, degree of vasodilatation, patient age, coexistence of other diseases, co-administration of other cytochrome P450 CYP3A-metabolized medications, fibroblast stimulation, and blood cell effects. Calcium antagonists are associated with a wide range of skin reactions, and the dermatologist should include these in the differential diagnosis of cutaneous diseases.