Table 1.

Glucocorticosteroid (GCS) Drug Interactions

Drug	Drug-Drug Interaction	Cytochrome Association	Renal Impairment	Hepatic Impairment
Prednisone Budesonide M-prednisolone Prednisolone Dexamethasone	Aminoglutethimide: decreases levels/therapeutic effects of GCS Amphotericin: increases hypokalemic effects of amphotericin B Antacid: may decrease the absorption of GCS Anticholinesterase: concurrent use can lead to profound weakness in myasthenia gravis patients Antidiabetic agents: may decrease hypoglycemic effects of diabetic medications Aprepitant: may increase serum levels/therapeutic effects of GCS Antifungal agents: may increase serum levels/therapeutic effects of GCS Barbiturates: may decrease levels/therapeutic effects of GCS Bile acid sequestrants: may reduce absorption of GCS Calcium channel blockers: may increase serum levels/therapeutic effects of GCS Cyclosporine: concurrent use may increase levels of cyclosporine Diuretics: hypokalemic effects may be increased Estrogens: may increase serum levels/therapeutic effects of GCS Fluoroquinolones: concurrent use can increase risk of tendinopathies (tendonitis, rupture), particularly in the elderly Isoniazid: decreased serum levels/therapeutic effects of GCS Macrolides: may increase serum levels/therapeutic effects of GCS Neuromuscular-blocking agents: concurrent use increases the risk of myopathy NSAIDs: concurrent use may lead to increased incidence of GI adverse effects Rifamycin derivatives: may decrease the levels/therapeutic effects of GCS Salicylates: concurrent use may increase GI adverse effects Thalidomide: concurrent use may increase the risk of toxic epidermal necrolysis and DVT Vaccine (dead organism): may decrease the effect of vaccines Vaccine (live organism): may increase the risk of infection. Usage of live vaccines is contraindicated in immunosuppressed patients Warfarin: concurrent use may increase anticoagulant effects Note: Corticosteroids interfere with calcium absorption. St. John's Wort may decrease corticosteroid levels.	Substrate of CYP3A4 Induces CYP2C19, 3A4	Use with caution— fluid retention may occur	Use with caution— fluid retention may occur

DVT

deep vein thrombosis

GI

gastrointestinal

NSAIDS

nonsteroidal anti-inflammatory drugs.