Rx Only
Rx Only
DESCRIPTION
The topical corticosteroids constitute a class of primarily
synthetic steroids used as antiinflammatory and antipruritic agents.
Anusol-HC 2.5% (Hydrocortisone Cream, USP) is a topical
corticosteroid with hydrocortisone 2.5% (active ingredient) in a
water-washable cream containing the following inactive ingredients:
benzyl alcohol, petrolatum, stearyl alcohol, propylene glycol, isopropyl
myristate, polyoxyl 40 stearate, carbomer 934, sodium lauryl sulfate,
edetate disodium, sodium hydroxide to adjust the pH, and purified water.
Hydrocortisone has the chemical name Pregn-4-ene-3,20-dione,
11,17, 21, trihydroxy-,(11ß) - and the following chemical
structure:
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CLINICAL PHARMACOLOGY
Topical corticosteroids share antiinflammatory, antipruritic and
vasoconstrictive actions.
The mechanism of antiinflammatory activity of the topical
corticosteroids is unclear. Various laboratory methods, including
vaso-constrictor assays, are used to compare and predict potencies
and/or clinical efficacies of the topical corticosteroids. There is some
evidence to suggest that a recognizable correlation exists between
vasoconstrictor potency and therapeutic efficacy in man.
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.
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