- Aminoglutethimide: Aminoglutethimide may lead to loss of corticosteroid-induced adrenal suppression.
- Amphotericin B: There have been cases reported in which concomitant use of Amphotericin B and hydrocortisone was followed by cardiac enlargement and congestive heart failure (see also Potassium depleting agents).
- Anticholinesterase agents: Concomitant use of anticholinesterase agents and corticosteroids may produce severe weakness in patients with myasthenia gravis. If possible, anticholinesterase agents should be withdrawn at least 24 hours before initiating corticosteroid therapy.
- Anticoagulant agents: Coadministration of corticosteroids and warfarin usually results in inhibition of response to warfarin, although there have been some conflicting reports. Therefore, coagulation indices should be monitored frequently to maintain the desired anticoagulant effect.
- Antidiabetic agents: Because corticosteroids may increase blood glucose concentrations, dosage adjustments of antidiabetic agents may be required.
- Antitubercular drugs: Serum concentrations of isoniazid may be decreased.
- CYP 3A4 inducers (e.g. barbiturates, phenytoin, carbamazepine, and rifampin): Drugs such as barbiturates, phenytoin, ephedrine, and rifampin, which induce hepatic microsomal drug metabolizing enzyme activity may enhance metabolism of prednisolone and require that the dosage of Flo-Pred be increased.
- CYP 3A4 inhibitors (e.g., ketoconazole, macrolide antibiotics): Ketoconazole has been reported to decrease the metabolism of certain corticosteroids by up to 60% leading to an increased risk of corticosteroid side effects.
- Cholestyramine: Cholestyramine may increase the clearance of corticosteroids.
- Cyclosporine: Increased activity of both cyclosporine and corticosteroids may occur when the two are used concurrently. Convulsions have been reported with concurrent use.
- Digitalis: Patients on digitalis glycosides may be at increased risk of arrhythmias due to hypokalemia.
- Estrogens, including oral contraceptives: Estrogens may decrease the hepatic metabolism of certain corticosteroids thereby increasing their effect.
- NSAlDS including aspirin and salicylates: Concomitant use of aspirin or other non-steroidal anti-inflammatory agents and corticosteroids increases the risk of gastrointestinal side effects. Aspirin should be used cautiously in conjunction with corticosteroids in hypoprothrombinemia. The clearance of salicylates may be increased with concurrent use of corticosteroids.
- Potassium depleting agents (e.g., diuretics, Amphotericin B): When corticosteroids are administered concomitantly with potassium-depleting agents, patients should be observed closely for development of hypokalemia.
- Skin tests: Corticosteroids may suppress reactions to skin tests.
- Toxoids and live or inactivated vaccines: Due to inhibition of antibody response, patients on prolonged corticosteroid therapy may exhibit a diminished response to toxoids and live or inactivated vaccines. Corticosteroids may also potentiate the replication of some organisms contained in live attenuated vaccines.
The effects of accidental ingestion of large quantities of prednisolone over a very short period of time have not been reported, but prolonged use of the drug can produce mental symptoms, moon face, abnormal fat deposits, fluid retention, excessive appetite, weight gain, hypertrichosis, acne, striae, ecchymosis, increased sweating, pigmentation, dry scaly skin, thinning scalp hair, increased blood pressure, tachycardia, thrombophlebitis, decreased resistance to infection, negative nitrogen balance with delayed bone and wound healing, headache, weakness, menstrual disorders, accentuated menopausal symptoms, neuropathy, fractures, osteoporosis, peptic ulcer, decreased glucose tolerance, hypokalemia, and adrenal insufficiency. Hepatomegaly and abdominal distention have been observed in children.
Treatment of acute overdosage is by immediate gastric lavage or emesis followed by supportive and symptomatic therapy. For chronic overdosage in the face of severe disease requiring continuous steroid therapy the dosage of prednisolone may be reduced only temporarily, or alternate day treatment may be introduced.