Prednisolone is a synthetic corticosteroid
drug which is usually taken orally and can be used for a large
number of different conditions. It has a mainly glucocorticoid
effect. The related substance prednisone is a pro-drug that is
converted by the liver into prednisolone, which is the active
drug.
Prednisolone is particularly effective as an immunosuppressant
and affects virtually all of the immune system. It can therefore
be used in autoimmune diseases, inflammatory diseases (such as
asthma and Crohn's disease), various kidney diseases including
nephrotic syndrome and to prevent and treat rejection in organ
transplantation.
Short-term side effects, as with all glucocorticoids, include
high blood glucose levels, especially in patients who already
have diabetes mellitus or are on other medications which
increase blood glucose (such as tacrolimus), and
mineralocorticoid effects such as fluid retention. Long term
side effects include Cushing's syndrome, weight gain,
osteoporosis, glaucoma, and type II diabetes mellitus.
Adrenal suppression occurs if prednisolone is taken for longer
than 7 days, a condition which means the body is unable to
synthesise natural corticosteroids and becomes dependent on the
prednisolone taken by the patient. For this reason, prednisolone
cannot be stopped abruptly if taken for longer than seven days,
but needs to be reduced slowly; this reduction may be over a few
days if the course of prednisolone was short, but may take weeks
or months if the patient has been on long-term steroid
treatment. Abrupt withdrawal will lead to an Addisonian crisis,
which may be life-threatening.
