Occupational exposure to propranolol: An unusual cause of allergic contact dermatitis
Citation: British Journal of Dermatology, July 2014, vol./is. 171/(131), 0007-0963 (July 2014)
Author(s): Ali F.R.; Shackleton D.B.; Kingston T.P.; Williams J.D.L.
Abstract: A 48-year-old man with no personal or family history of atopy presented with a 6-month history of facial and hand dermatitis. For 3 years, the patient had been working in a pharmaceutical factory in which he was exposed to a variety of medicaments including propranolol, ethylcellulose, hypromellose and microcrystalline cellulose. The history was consistent with occupational exposure to an allergen, with improvement of symptoms seen during absences from work. He was patch tested to the hospital standard battery, face series, relevant parts of the textile series, and breakdown products of fragrance mixes 1 and 2, together with the medicaments and items of uniform he was exposed to at work and a variety of his own products appropriately applied. Positive reactions were elicited by propranolol hydrochloride in 1% white soft paraffin and colophony. Colophony was believed to be of old relevance, with a previous history of reactions to plasters reported. In retrospect, the operator had been involved in the manufacture of coated propranolol spheroids.
The job involved a multistage batch process to mix propranolol powder with various excipients followed by extrusion and spheronization. The spheroids were dried and coated before being filled into capsules. While protective clothing was mandatory, potential for skin exposure existed, for example, by inadvertently touching the face with a gloved hand or from contamination of work surfaces. Following a move to a different area of the factory in which propranolol was not being used, the symptoms greatly improved. Contact allergy to a variety of beta-blockers has been reported previously, with three cases of contact allergy to propranolol reported in workers within the pharmaceutical industry. Propranolol is regarded to have slight skin irritancy properties but was not widely regarded to be a significant skin sensitizer. This unusual form of contact allergen should be considered in pharmaceutical workers.
Publication Type: Journal: Conference Abstract
Full Text: Available from Wiley in British Journal of Dermatology