Corticosteroids

Corticosteroids

Corticosteroids are anti-inflammatory drugs available in inhaledand systemic forms for the short- and long-term control of asthma symptoms. Many products with differing potencies are available.

§    Inhaled corticosteroids include:

§    beclomethasone dipropionate

§    budesonide

§    flunisolide

§    fluticasone

§    triamcinolone acetonide.

Oral corticosteroids include:

§    prednisolone

§    prednisone.

§    I.V. corticosteroids include:

§    hydrocortisone sodium succinate

§    methylprednisolone sodium succinate.

Pharmacokinetics

Oral prednisone is readily absorbed and extensively metabolized in the liver to the active metabolite prednisolone. The I.V. form has a rapid onset. Inhaled drugs are minimally absorbed, although absorption increases as the dosage is increased.

Pharmacodynamics

Corticosteroids work by inhibiting the production of cytokines, leukotrienes, and prostaglandins; the recruitment of eosinophils; and the release of other inflammatory mediators. They also affect other areas in the body, which can cause long-term adverse reac-tions. (See Corticosteroids.)

Pharmacotherapeutics

Corticosteroids are the most effective drugs available for the long-term treatment and prevention of acute asthma attacks.

Inhalation for prevention

Inhaled corticosteroids are the preferred drugs for preventing fu-ture attacks in the patient with mild to severe asthma. Use of in-haled corticosteroids reduces the need for systemic steroids in many cases, thus reducing the patient’s risk of developing serious long-term adverse reactions.

Systemic for the serious

Systemic forms are usually reserved for moderate to severe at-tacks, but they’re also used in the patient with milder asthma that fails to respond to other measures. Systemic corticosteroids should be used at the lowest effective dosage and for the shortest period possible to avoid adverse reactions.

Drug interactions

Interactions are uncommon when using inhaled forms.

·                 Hormonal contraceptives, ketoconazole, and macrolide antibi-otics may increase the activity of corticosteroids in general, result-ing in the need to decrease the steroid dosage.

·                 Barbiturates, cholestyramine, rifampin, and phenytoin may de-crease the effectiveness of corticosteroids, resulting in the need to increase the steroid dosage. (See Adverse reactions to inhaledcorticosteroids.)