Prednisone is a glucocorticoid medication mostly used to suppress the immune system and decrease inflammation in conditions such as asthma, COPD, and rheumatologic diseases. It is also used to treat high blood calcium due to cancer and along with other steroids for adrenal insufficiency. It is taken by mouth.
Common side effects with long term use include cataracts, bone loss, easy bruising, muscle weakness, and thrush. Other side effects include weight gain, swelling, high blood sugar, and psychosis. It is generally considered safe in pregnancy and low doses appear to be okay when breastfeeding. After prolonged use prednisone needs to be stopped gradually.
Prednisone must be converted to prednisolone by the liver before it becomes active. Prednisolone than binds to glucocorticoid receptors, activating them and triggering changes in gene expression.
Prednisone was patented in 1954 and approved for medical use in the United States in 1955. It is available as a generic medication. In the United States the wholesale cost per dose is less than US$0.30 as of 2018. In 2016 it was the 31st most prescribed medication in the United States with more than 23 million prescriptions.
Prednisone is used for many different autoimmune diseases and inflammatory conditions, including: asthma, COPD, CIDP, rheumatic disorders, allergic disorders, ulcerative colitis and Crohn’s disease, adrenocortical insufficiency, hypercalcemia due to cancer, thyroiditis, laryngitis, severe tuberculosis, urticaria (hives), lipid pneumonitis, pericarditis, multiple sclerosis, nephrotic syndrome, sarcoidosis, to relieve the effects of shingles, lupus, myasthenia gravis, poison oak exposure, Ménière’s disease, autoimmune hepatitis, giant-cell arteritis, the Herxheimer reaction that is common during the treatment of syphilis, Duchenne muscular dystrophy, uveitis, and as part of a drug regimen to prevent rejection after organ transplant.
Prednisone has also been used in the treatment of migraine headaches and cluster headaches and for severe aphthous ulcer. Prednisone is used as an antitumor drug. It is important in the treatment of acute lymphoblastic leukemia, non-Hodgkin lymphomas, Hodgkin’s lymphoma, multiple myeloma, and other hormone-sensitive tumors, in combination with other anticancer drugs.
Prednisone can be used in the treatment of decompensated heart failure to increase renal responsiveness to diuretics, especially in heart failure patients with refractory diuretic resistance with large dose of loop diuretics. In terms of the mechanism of action for this purpose: prednisone, a glucocorticoid, can improve renal responsiveness to atrial natriuretic peptide by increasing the density of natriuretic peptide receptor type A in the renal inner medullary collecting duct, inducing a potent diuresis.
Short-term side effects, as with all glucocorticoids, include high blood glucose levels (especially in patients with diabetes mellitus or on other medications that increase blood glucose, such as tacrolimus) and mineralocorticoid effects such as fluid retention. The mineralocorticoid effects of prednisone are minor, which is why it is not used in the management of adrenal insufficiency, unless a more potent mineralocorticoid is administered concomitantly.
It can also cause depression or depressive symptoms and anxiety in some individuals.
Long-term side effects include Cushing’s syndrome, steroid dementia syndrome, truncal weight gain, osteoporosis, glaucoma and cataracts, diabetes mellitus type 2, and depression upon dose reduction or cessation.
Adrenal suppression will begin to occur if prednisone is taken for longer than seven days. Eventually, this may cause the body to temporarily lose the ability to manufacture natural corticosteroids (especially cortisol), which results in dependence on prednisone. For this reason, prednisone should not be abruptly stopped if taken for more than seven days; instead, the dosage should be gradually reduced. This weaning process may be over a few days if the course of prednisone was short, but may take weeks or months if the patient had been on long-term treatment. Abrupt withdrawal may lead to an Addison crisis. For those on chronic therapy, alternate-day dosing may preserve adrenal function and thereby reduce side effects.
Glucocorticoids act to inhibit feedback of both the hypothalamus, decreasing corticotropin-releasing hormone [CRH], and corticotrophs in the anterior pituitary gland, decreasing the amount of adrenocorticotropic hormone [ACTH]. For this reason, glucocorticoid analogue drugs such as prednisone down-regulate the natural synthesis of glucocorticoids. This mechanism leads to dependence in a short time and can be dangerous if medications are withdrawn too quickly. The body must have time to begin synthesis of CRH and ACTH and for the adrenal glands to begin functioning normally again.
The magnitude and speed of dose reduction in corticosteroid withdrawal should be determined on a case-by-case basis, taking into consideration the underlying condition being treated, and individual patient factors such as the likelihood of relapse and the duration of corticosteroid treatment. Gradual withdrawal of systemic corticosteroids should be considered in those whose disease is unlikely to relapse and have:
- received more than 40 mg prednisone (or equivalent) daily for more than 1 week
- been given repeat doses in the evening;
- received more than 3 weeks’ treatment
- recently received repeated courses (particularly if taken for longer than 3 weeks)
- taken a short course within 1 year of stopping long-term therapy
- other possible causes of adrenal suppression
Systemic corticosteroids may be stopped abruptly in those whose disease is unlikely to relapse and who have received treatment for 3 weeks or less and who are not included in the patient groups described above.
During corticosteroid withdrawal, the dose may be reduced rapidly down to physiological doses (equivalent to prednisolone 7.5 mg daily) and then reduced more slowly. Assessment of the disease may be needed during withdrawal to ensure that relapse does not occur.