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Corticosteroids |   |
| Steroids comprise five general groups of complex organic compounds which are produced in the adrenal cortex. The group that has clinical relevance to respiratory therapy are the glucocorticoids. Cortisol and glucocortioids regulate the metabolism of carbohydreates, fats, and proteins to generally increase levels of glucose for energy to be used by the body. That is why cortisol and its analogues are called glucocorticoids. |  |
One of the major therapeutic effects seen with analogues of natural adrenal cortical hormone hydrocortisone is an antiinflammatory action. Glucocorticoid analogs are used for their antiinflammatory effects in treating asthma, which is basically a disease in which there is chronic inflammation of the airway wall which causes airflow limitation and hyperresponsiveness to a variety of stimuli.
Steroids can be administered orally, intravenously (IV), or aerosolized for respiratory symptoms. The IV drug of choice is usually hydrocortisone or methylprednisolone. Oral drug of choice is prednisone or prednisolone. Aerosolized corticosteroid preparations that have antiinflammatory effectiveness in the treatment of asthma include: hydrocortisone, cortisone, prednisone, prednisolone, and methylprednisolone.
In treating respiratory diseases, steroids are administered orally for more significant exacerbations of bronchospasms, and by IV for serious bronchospasm. However, the potential side effects of systemic administration of corticosteroid treatments are well recognized, and include:
- HPA suppression
- immunosupression
- increased glucose levels
- fluid retention
- hypertension
- increased white blood cell count
- peptic ulcer
- osteoporosis
- psychiatric reactions
- growth retardation
- myopathy of skeletal muscle
- cataract formation
- dermatologic changes
The quantity, severity, and frequency with which these complicating side effects appear when systemic steroid treatments are used have provided the motivation for transferring patients to aerosolized, inhaled steroids whenever possible. The introduction of synthetic analogues of hydrocortisone, which have a high topical antiinflammatory activity, have paved the way for effectively using aerosolized steroids with little systemic side effects. These drugs include: beclamethasone, triamcinolone, flunisolide, budesonide, and fluticasone.