Taste loss to terbinafine: a case-control study of potential risk factors.

1. To identify risk factors associated with taste loss to terbinafine, we performed a case-control study of 87 reports of probably terbinafine-induced taste loss and 362 controls on terbinafine without taste loss, who had filled prescriptions from the same pharmacy and GP. Data on general health, diet, alcohol, smoking, drug use and medical history were collected by means of a self-administered questionnaire. 2. The mean latent period between first intake of terbinafine and taste loss was 35 days. Most patients recovered within 4 months after discontinuation. Cases were significantly older than controls. The odds ratio of taste loss in patients of 65 years and older was 4.4 in comparison with persons younger than 35 years of age (95% CI: 1.4-16.1). The risk in persons with a body mass index (BMI) below 21 kg m-2 was 4.4 times higher than in those with a BMI of more than 27 kg m-2 (95% CI: 1.6-14.2). The risk of taste loss in patients of 55 years and older with a BMI below 21 kg m-2 was 12.8 times higher than that in patients below 35 years of age (95% CI: 1.9-88.6). 3. A low BMI, a history of taste loss, and ageing are risk factors for developing taste loss to terbinafine. Prescription of this drug to elderly patients with low BMI and low daily intake of nutrients requires careful follow-up.