Topical timolol-induced interstitial pneumopathy

Timolol maleate is a beta-blocker widely used in topical administration for open angle glaucoma. We report a case of interstitial pneumopathy which de veloped in a 58-year-old patient who was given timolol eyedrops (2 drops b. i.d. since 1986). The patient presented,vith cough and dyspnea and was foun d to have a restrictive disorder leading to hypoxemia (68 mmHg at rest and 51 minHg during exercise). Bronchial lavage fluid had high lymphocyte (28%) and nentrophil (7%) counts. Transbronchial biopsies demonstrated moderate fibrous thickening of the inter-alveolar walls. Timolol eyedrops were stopp ed. Three months Inter; the patient was asymptomatic with normal lung funct ion, chest chi-ray and thoracic CT-scan.