The effects of cortisone,
dexamethasone, fludrocortisone,
hydrocortisone, methyl-
prednisolone,
prednisolone and
prednisone can be markedly reduced by rifampicin. The UK manufacturers and the CSM in the UK suggest that
rifabutin may interact similarly, although this is likely to be to a lesser extent.
The significance of the falls in corticosteroid levels will depend on the disease the corticosteroid is prescribed for. Monitor the outcome of concurrent use closely, especially in transplant patients, and increase the dose accordingly. Topical preparations are not likely to be affected.