The absorption of prednisone
can be reduced by large (60 mL) but not small doses of aluminium/magnesium hydroxide antacids
. Prednisolone probably behaves similarly. Dexamethasone absorption is reduced by about 75% by magnesium trisilicate.
Some manufacturers of dexamethasone
suggest that the doses of antacid should be separated as far as possible from the dexamethasone
. In other similar antacid interactions 2 to 3 hours is usually sufficient. The manufacturers of deflazacort also issue a similar warning. It would seem prudent to follow this advice for large doses of antacid and any corticosteroid. Concurrent use should be monitored to confirm that the therapeutic response is adequate.