Metoprolol

An 18-year-old male with asymptomatic hypertension and chronic glomerulonephritis began treatment with metoprolol (50mg twice daily), potassium chloride, and sodium bicarbonate supplements. Approximately 4 to 6 weeks after starting metoprolol, he experienced hair loss which escalated to significant diffuse alopecia within 2 weeks. A scalp biopsy indicated telogen effluvium. After discontinuing metoprolol and starting on hydralazine, and later adding propranolol, the patient's alopecia began to improve 2 months following the cessation of propranolol, which was 6 months after stopping metoprolol. The presence of transverse depressions in the patient's finger- and toenails was also noted. The case suggests that metoprolol and propranolol, both ß-adrenergic antagonists, may share a common mechanism that contributes to alopecia.