Drugs that affect steroid dose requirements

Some drugs, for example rifampicin, phenytoin and carbamazepine, increase steroid metabolism in the liver, increasing glucocorticoid and mineralocorticoid dose requirements.

Other drugs, such as some azole antifungals and some protease inhibitors, decrease steroid metabolism in the liver and reduce glucocorticoid and mineralocorticoid dose requirements.

Long-term use of a nonsteroidal anti-inflammatory drug (NSAID) predisposes the patient to hyperkalaemia, and can exacerbate the fluid retention and elevated blood pressure caused by fludrocortisone.