Cutaneous reactions to propranolol (Inderal).

Six patients wit psoriasiform cutaneous eruptions that developed during long-term therapy with propranolol (Inderal) have been studied. The cutaneous changes closely resembled those seen during treatment with practolol (Eraldin). The duration of treatment before the rash was recognized averaged 10 months, which is about the same latency period as in patients with practolol-induced exanthemas. The exanthemas disappeared gradually within 1-5 weeks after treatment with propranolol had been stopped. In 4 of 5 patients the skin eruptions reappeared within 2-4 days after oral challenge with propranolol. In the fifth patient, who developed a rash after challenge with practolol and severe abdominal colics after challenge with oxprenolol, no further provocation tests with propranolol were attempted. Skin biopsies obtained from 3 patients showed a microscopical picture similar to that seen in practolol exanthemas. The pathogenetic mechanism responsible for these adverse cutaneous reactions is unknown. However, since the possibility exists, that these changes may be caused by blockade of the epidermal beta-receptors, it is recommended that all patients receiving beta-blocking drugs should be examined carefully for similar adverse reactions. Special attention should be drawn to the reversible skin changes, since during treatment with practolol these have often preceded serious complications from other organs.