The realisation and reliability of the halothane-caffeine contracture tests in children to detect the susceptibility to malignant hyperthermia (MH) is still controversial. The present study concerned 26 children aged 2 to 13 years, (mean 9.5 +/- 1.3 years) who were tested either because of a personal symptomatology (14 cases) or as a member of a susceptible MH family (12 cases). Half of the children had a positive test (MHS and MHE) as is found in adults. Furthermore comparison of threshold concentrations of halothane and caffeine as well as the 32 nmol caffeine-induced contractures dit not show significant differences related to age. These results support the possibility to perform under good conditions and with good reliability the diagnostic test of susceptibility to malignant hyperthermia in children from 2 years on.