ObjectiveTo assess whether chronic long-term calcium antagonist therapy may increase genotoxicity, the chromosome aberration test, a widely accepted genotoxic assay, was usedex vivoin peripheral human lymphocytes of patients with or without long-term exposure to calcium antagonist therapy.Methods and resultsIn a case–control study design, we evaluated 30 ischaemic and/or hypertensive patients (22 males, eight females; age 59.4 ± 1.5 years), under chronic calcium antagonist treatment (group I), for more than 3 years (4.4 ± 0.34 years) and 30 age-matched subjects, without any previous exposure to calcium antagonists (group II). Venous blood samples were collected from the patients and cultures were set up for cytogenetic analysis by standard methods.For each subject, 100 metaphases were scored. The two groups showed similar values (mean ± SEM) for percentage aberrant cells (group I 2.6 ± 0.3 versus group II 2.5 ± 0.3, not significant), percentage structural aberrations (group I 1.9 ± 0.3 versus group II 1.8 ± 0.2, not significant) and percentage numerical aberrations (group I 0.70 ± 0.2 versus group II 0.73 ± 0.2, not significant).ConclusionsLong-term calcium antagonist therapy is not associated with an increased incidence of chromosomal indices of genotoxic damage in humans.