Corticosteroid agents mimic the endogenous steroid hormones produced in the adrenal cortex—including:
Mineralocorticoids (aldosterone) are primarily regulated by the renin-angiotensin system and possess salt-retaining properties.
Glucocorticoids (cortisol) are primarily regulated by ACTH and can have anti-inflammatory effects, as well as several metabolic and immunogenic effects, on the body.
While several corticosteroid agents possess properties of both hormones,
fludrocortisone is most commonly used for its mineralocorticoid activity .
hydrocortisone, cortisone, prednisone and prednisolone are used for their glucocorticoid effects.
The corticosteroids are used widely in medicine largely for their potent antiinflammatory and immunosuppressive activities.
Short-acting products such as hydrocortisone are the least potent.
Prednisone and methylprednisolone, which are intermediate-acting products, are four to five times more potent than hydrocortisone.
Dexamethasone is a long-acting, systemic corticosteroid; its potency is about 25 times greater than the short-acting products.
Prednisone, prednisolone, methylprednisone and triamcinolone:
*Are synthetic glucocorticoids
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are the most commonly used oral agents as they are inexpensive,
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rapid in onset,
*intermediate in duration of action.
*have potent glucocorticoid with minimal mineralocorticoid activities, as compared to cortisone and hydrocortisone.
*widely used in the therapy of severe inflammation, autoimmune conditions, hypersensitivity reactions and organ rejection.
Prednisone ( Hostacortin 5mg tab)® is converted to prednisolone, its active form, in the liver.
Prednisolone ( Hostacortin-H, Solupred 5mg tab)®, Xilone &Xilone fort, predsol &predsol fort syrup…).®
Methylprednisolone is available in multiple forms in
tablets of 2, 4, 8, 16 and 32 mg ®Medrol and in Medrol Dosepaks (21 tablets of 4 mg each). Injectable forms of methylprednisolone are also available ® Solu-Medrol and Depo-Medrol ®.
Triamcinolone is used in topical ( e.g.Topicort cream®, solutions and aerosols for therapy of allergic and hypersensitivity reactions and control of inflammation as well as in parenteral formulations Parenteral forms for injection (Aristocort and Kenacort 4mg tab or 40mg vial )® amcinol vial 40 mg.)®… .
Betamethasone and dexamethasone:
- have greater glucocorticoid potency and less aldosterone-like activity than prednisone,
*have a longer duration of action,
- they are mostly used in topical or liquid forms for local application and in injectable forms for severe hypersensitivity reactions and inflammation.
Dexamethasone is a synthetic glucocorticoid that is used parenterally as therapy of severe hypersensitivity reactions, shock and control of severe inflammation. Dexamethasone is available in multiple forms for injection including Decadron & Fortecortin ®. Available also in many topical forms.
Betamethasone is available in solution for injection ( e.g. Celestone, Diprofos, Betafos)® and in multiple generic forms as syrups and effervescent tablets for oral use (e.g. Betasone tab ® , edemas and foams for rectal use, aerosols for nasal and respiratory use, and creams and lotions for topical use (e.g. Betamethasone, betaval , Betaderm cream & ointment ®
Hydrocortisone ( e.g. Solucortif vial) ®:
*Also available in topical forms (e.g. hydrocortisone, micort cream ®
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rapid and short acting glucocorticoid that is used for therapy of adrenal insufficiency and in treatment of allergic and inflammatory conditions.
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has the same chemical structure as cortisol and thus most closely resembles the human adrenal hormone.
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has both glucocorticoid and mineralocorticoid properties.
Methylprednisone and hydrocortisone:
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are most commonly used for intravenous administration,
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typically given in emergency or critical situations in which rapid and profound immunosuppression or antiinflammatory activity is needed.
Mineralocorticoids:
** primarily act on the distal tubules and collecting ducts of kidneys, beside their actions on gut, salivary
and sweat glands, where they stimulate reabsorption of sodium and excretion of potassium and hydrogen ions,
thus maintaining electrolyte balance.
**MC deficiency leads to sodium wasting, contraction of extracellular volume, hyponatremia, hyperkalemia and acidosis.
Fludrocortisone ( Cortilon, florinef 0.1mg tab)® is the synthetic MC used in all patients with primary adrenal insufficiency and classic
congenital adrenal hyperplasia.
- Fludrocortisone has10 times glucocorticoid effect & 125 times mineralocorticoid effect as hydrocortisone.
Stress dosing of steroids:
With stress, cortisol secretion increases. Consequently, all patients with primary or secondary adrenal insufficiency and CAH must be educated about the need for increasing their GC dose during stress to avoid an adrenal crisis, which can be fatal.
Short-term, low-dose steroid therapy rarely results in any of the adverse effects, However, as the dosage or duration of therapy increases, so does the risk of undesirable effects.
In long-term therapy, alternate-day administration should be considered if possible according to the indication.
the goal of steroid therapy should be to maintain the lowest dosage that results in adequate clinical response and to discontinue therapy by tapering the drug when a patient’s disease state allows.