Pharmacokinetics: The extent of percutaneous absorption of topical corticosteroids is determined by many factors including the vehicle, the integrity of the epidermal barrier, and the use of occlusive dressings. Topical corticosteroids can be absorbed from normal intact skin. Inflammation and/or other disease processes in the skin increase percutaneous absorption. Occlusive dressings substantially increase the percutaneous absorption of topical corticosteroids. Thus, occlusive dressings may be a valuable therapeutic adjunct for treatment of resistant dermatoses (See DOSAGE AND ADMINISTRATION ). Once absorbed through the skin, topical corticosteroids are handled through pharmacokinetic pathways similar to systemically administered corticosteroids. Corticosteroids are bound to plasma proteins in varying degrees. Corticosteroids are metabolized primarily in the liver and are then excreted by the kidneys. Some of the topical corticosteroids and their metabolites are also excreted into the bile .
If too much corticosteroid cream becomes absorbed through the skin, serious complications can result, including adrenal gland suppression and Cushing's syndrome. In adrenal gland suppression, the body stops manufacturing its own steroids, so the patient may become dependent on the drug. Cushing's syndrome causes symptoms including diabetes, high blood pressure, and muscle weakness. Local side effects are also possible due to misuse of corticosteroid cream. These can include skin atrophy, stretch marks , susceptibility to infection, allergy , easily bruised or injured skin, and enlarged blood vessels.