The effect of prednisone may be reduced by anticonvulsants, phenobarbital, phenytoin, antihistamines, barbiturates, ephedrine, primidone and rifampicin.
The efficacy of hypoglycemics, diuretics, salicylates and anticholinesterases may be reduced by prednisone.
Prednisone when taken with azathioprine provides salutary effects. Aspirin and estrogen may enhance the effect of prednisone. The dose of prednisone is reduced when taking cyclosporine, an immunosuppressant.