Glucocorticoids have become the cornerstone of therapy
of both asthma and allergic rhinitis.
The exact mechanism is not known and may include:
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They suppress the immune mechanism and reduce antibody synthesis.
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Potentiate the effect endogenous catecholamines by preventing their non neuronal uptake and increase number of B-receptors.
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Inhibition of the influx of inflammatory cells into the lung and inhibition of the release of mediators from macrophages and eosinophils.
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Also, corticosteroids prevent the formation of bronchoconstircting PGs, LTs and platelets activating factor by inhibiting phospholipase A2 enzyme.
Indications Z
all types of asthma: may be used systemically as hydrocortisone, prednisolone, dexamethazone; strongest action
or by inhalation as beclomethazone, fluticasone and triamcinolone (By this method, the drugs exert local action with minimal systemic absorption and reduced adverse effects).
Adverse effects:
These occur if high doses of systemic corticosteroids are used for long duration. They include:
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Adrenal suppression, Cushing syndrome, weight gain, salt and water retention, immunosuppression with flare of infection, depression, psycosis, growth retardation in children, peptic ulcer and cataract.
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Oropharyngeal candidiasis can occur after inhaled corticosteroid. To be avoided; use mouth wash and gargle after each inhalation. If Candida infection occurs.