RESUMO
INTRODUCTION: Pleural effusions can be caused by several conditions such as cancer, connective tissue disease, and infection. They are occasionally caused due to the adverse drug reaction. Most commonly, systemic minoxidil use can cause pleural effusions in patients with chronic kidney disease. CASE PRESENTATION: We present a case of a patient without chronic kidney disease who developed pleural effusion as a result of unintentional use of topical minoxidil orally. The patient's oxygen saturation was 90% on room air; there was dullness to percussion and asymmetrical chest expansion with diminished air entry on both sides. In chest x-ray there were bilateral pleural opacities. Minimal pleural effusions were shown in ultrasonography of the chest. The patient was managed with diuretics and airway management which resolved completely. CONCLUSION: Minoxidil is a commonly used drug by many people for the treatment of hair fall with or without doctor advice. We would like to stress that even though rare, physicians/pulmonologists should be aware of the rare side effects of topical minoxidil, and it should be kept in mind as a differential diagnosis for pleural effusion.