Corticosteroids potency

Metabolites (Activity) beclomethasone 17-mono-propionate (active), free beclome-thasone (very weak anti-inflammatory effects) 16 -hydroxy-prednisolone and 6 -hydroxy-budesonide (< 1 % of parent) 67-OH (low corticosteroid potency) ... 

Topical corticosteroids vary in potency, depending on tiie concentration of the drug (percentage), the vehicle in which the drug is suspended (lotion, cream, aerosol spray), and the area to which the drug is applied (open or denuded skin, unbroken skin, thickness of the skin over tiie treated area). 

Both of these agents have been associated with rare reports of Churg-Strauss syndrome. This syndrome may result from the corticosteroid dose reduction, as it has also been reported when systemic corticosteroids have been reduced or withdrawn in conjunction with the initiation of high-potency inhaled corticosteroids.35... 

It is important to remember that adverse effects of topical corticosteroids may be systemic in nature and hypothalamic-pituitary-adrenal axis suppression can occur, especially when high-potency corticosteroids are used. Infants and small children may be more susceptible due to their increased skin sur-face body mass ratio.18 Topical corticosteroids may also cause striae, skin atrophy, acne, telangiectasias, and rosacea.2,10,18 Atrophy can result in thin, fragile, easily lacerated skin. Striae are caused by tearing of dermal connective tissue and are irreversible.18 Due to their significant adverse-effect profile, it has been recommended that no topical corticosteroid be used regularly for more than 4 weeks without review and reassessment.2... 

Erythema, inflammation, pain, and itching caused by contact dermatitis can be effectively treated with topically applied corticosteroids. With such a wide range of products and potencies available, an appropriate steroid selection is based on severity and location of the lesions. Table 62-6 shows a list of topical steroids and their potencies. Higher-potency preparations are used in areas where penetration is poor, such as on the elbows and knees. Lower-potency products should be reserved for areas of higher penetration, such as on the face, axillae, and groin. Low-potency steroids are also recommended for the treatment of infants and children.32,33... 

Corticosteroids Dosage Forms Strength (%) USP Potency Ratings3 Vasoconstrictive Potency Rating ... 

High-potency preparations are used primarily as alternatives to systemic corticosteroids when local therapy is feasible. 

Corticosteroids Dosage Forms/Strength (°/o) Ratings0 Potency Rating6... 

Selected Topical Corticosteroids and Vasoconstricting Potency (Continued)... 

Topical corticosteroids may be used for short-term treatment of acute flare-ups (see Table 16-1 in Chap. 16 on Psoriasis). Most corticosteroids are applied once or twice daily. High-potency agents are used for less than 3 weeks for flare-ups or for lichenified (thickened) lesions. Moderate-potency steroids may be used for more chronic conditions, and low-... 

Inhaled corticosteroids are the preferred long-term control therapy for persistent asthma in all patients because of their potency and consistent effectiveness they are also the only therapy shown to reduce the risk of death from asthma. Comparative doses are included in Table 80-3. Most patients with moderate disease can be controlled with twice-daily dosing some products have once-daily dosing indications. Patients with more severe disease require multiple daily dosing. Because the inflammatory response of asthma inhibits steroid receptor binding, patients should be started on higher and more frequent doses and then tapered down once control has been achieved. The response to inhaled corticosteroids is delayed symptoms improve in most patients within the first 1 to 2 weeks and reach maximum improvement in 4 to 8 weeks. Maximum improvement in FEVj and PEF rates may require 3 to 6 weeks. 

Q51 is available as a low-potency corticosteroid for topical administration to the skin... 

Furuncles (boils) are caused by staphylococci. Fusidic acid is very effective against boils. Hydrocortisone is a lov/-potency corticosteroid. Aciclovir (antiviral) is indicated for the treatment and prophylaxis of herpes infections. Promethazine is an antihistamine cream and zinc oxide acts as a barrier v/hen used in creams. 

Relative Potency of Selected Topical Corticosteroid Products... 

Various synthetic corticosteroids have also been developed. Some display greater potency than the native steroids, while others exhibit glucocorticoid activity with little associated mineralocorticoid effects, or vice versa. The major glucocorticoids used clinically are synthetic. They are usually employed as ... 

Corticosteroid Relative sodium-retaining potency Relative antiinflammatory potency Approximately equivalent IV or oral doses (mg) Approximate plasma half-Ufe (hours) Biological half-life (hours)... 

Numerous glucocorticosteroids for topical application are available. Essentially they all suppress the symptoms of inflammatory and hypersensitivity reactions and their mechanism of action is similar. Their indications include seborrhoeic and atopic dermatitis, phototoxic reactions, psoriasis, chronic discoid lupus, hypertrophic lichen planus and alopecia areata. However it has to be kept in mind that the use of corticosteroids for these conditions in most cases only gives symptomatic relieve and that the problem tends to recur on cessation of therapy. Traditionally topical corticosteroid formulations are grouped according to approximate relative efficacy. This efficacy is determined by both the potency of the agent and the concentration in which the corticosteroid is used. 

Topical preparations usually contain relatively insoluble steroids, such as clobetasol propionate, triamcinolone acetonide, or triamcinolone diacetate. Side effects of this mode of drug application are usually milder and more transient than those seen after systemically administered steroids. However, potent topical corticosteroids, such as clobetasol propionate (Temovate), can suppress adrenal function when used in large amounts for a long time, especially when the skin surface is denuded or when occlusive dressings are employed. Since the high potency topical preparations carry a higher risk of local side effects, their use should be held in reserve. 

Mechanism of Action Ahigh-potency.fluoronated topical corticosteroid that has antiinflammatory, antipruritic, and vasoconstrictive properties. The exact mechanism of the anti-inflammatoryprocess is unclear TherapeuticEffect Reduces tissue response to the inflammatory process. 

Corticosteroids Anti-inflammatory potency Sodium-retaining potency... 

The remarkable efficacy of topical corticosteroids in the treatment of inflammatory dermatoses was noted soon after the introduction of hydrocortisone in 1952. Numerous analogs are now available that offer extensive choices of potencies, concentrations, and vehicles. The therapeutic effectiveness of topical corticosteroids is based primarily on their antiinflammatory activity. Definitive explanations of the effects of corticosteroids on endogenous mediators of inflammation await further experimental clarification. The antimitotic effects of corticosteroids on human epidermis may account for an additional mechanism of action in psoriasis and other dermatologic diseases associated with increased cell turnover. The general pharmacology of these endocrine agents is discussed in Chapter 39. 

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