Hypomagnesaemia: an underdiagnosed interaction between gentamicin and cytotoxic chemotherapy for acute non-lymphoblastic leukaemia.

Abstract

Hypomagnesaemia occurred in 6 of 11 leukaemic patients who received gentamicin. This problem has been reported relatively infrequently when gentamicin is used alone. Our hypomagnesaemic patients received concurrent courses of gentamicin with cytotoxic therapy significantly more often but it is not clear whether this represents a true drug interaction or an interaction between gentamicin and the products of cell lysis produced by cytotoxic treatment. The incidence of this problem has been underestimated previously because hypocalcaemia was used as an indicator. Renal wasting of magnesium is well documented as the mechanism by which the hypomagnesaemia is sustained but further investigation is required to see whether other factors are involved in its initiation.