Both aluminium hydroxide and aluminium/magnesium hydroxide can cause a small reduction in the absorption of ethambutol
(e.g. AUC decreased by 10%) in some patients.
The reduction in absorption is generally small and variable, and it seems doubtful if it will have a significant effect on the treatment of tuberculosis
. However, the US manufacturer suggests that aluminium hydroxide-containing antacids
should not be taken until 4 hours after a dose of ethambutol