Topical corticosteroids are synthetic drugs that resemble naturally-occurring hormones in the body. Corticosteroids are the most frequently prescribed treatment for psoriasis of mild to moderate severity because they decrease the rate at which skin cells grow and reduce inflammation, thereby also relieving the itch that often accompanies psoriasis.
Types of Topical Steroids
Topical corticosteroids vary in potency—from extremely mild to very strong—and come in several forms, including creams, gels, lotions, sprays and ointments. There are even therapeutic corticosteroid- impregnated tapes (Cordran), which are particularly useful for lichenified (thick) plaques that are refractory to other topical corticosteroids. Topical steroids have to be handpicked according to the stage of psoriasis, its extend and site of involvement. When the thickness of scales decreases, the strength of corticosteroids should also be reduced proportionally.
Systemic Side Effects of Topical Steroids
- Adrenal suppression:Because of the absorption of potent steroids into the blood stream, the adrenal glands would become suppressed and their production of normal steroids will suffer as a result. This can have far reaching effects on the body.
- Tachyphylaxis:The body develops resistance to the topical application after some time.
Topical Side Effects of Topical Steroids
- Thinning of skin.
- Dilation of capillaries that are shown through the thinned skin.
- Stretching and splitting of the skin causing stretch marks.
- Pimple-like eruptions on the treated area, especially on the face, chest, back and limbs-called steroid acne.
- The main problem with topical (and systemic steroids) is the rebound phenomenon or exacerbation of the lesions that occur if the steroids are suddenly stopped or withdrawn. A localized form of psoriasis can become generalized or a generalized form can get precipitated as pustular or erythrodermic forms when steroids are withdrawn.
How to Avoid Side Effects of Topical Steroid
- Combination and sequential therapies: Corticosteroids are alternated or combined with other anti psoriatics like calcipotriene and tazarotene so as to reduce the cumulative effects as well as the tachyphylaxis.
- Use of graded strengths of corticosteroids will help in avoiding the topical side effects like atrophy (thinning) and stretch marks.
- Gradual withdrawal and replacement with other safer applications .
- Reserve use of systemic steroids only for severe forms like pustular, erythrodermic and arthritic forms of psoriasis.
To prevent side effects of super potent corticosteroids, Katz et al developed a regimen in which a super potent corticosteroid, betamethasone dipropionate in an optimized base, was applied 3 times over a 24-hour period each week. With that regimen, which has been called “weekend therapy” or “pulse therapy”, improvement in psoriasis was maintained for up to 6 months in 60% of patients treated this way, compared with 20% of patients treated with placebo. Long-term treatment of face and intertriginous sites, for example, remains problematic because these areas are more susceptible to local cutaneous side effects of topical corticosteroids. After an initial 2-week treatment period, a novel maintenance regimen involving application of fluticasone propionate ointment once daily on two consecutive days each week maintained improvement in psoriasis for up to 10 weeks. Regimens with even longer maintenance periods are currently under study.
Most recently, a new vehicle has been developed for the delivery of topical corticosteroids. Betamethasone valerate in a foam (Luxiq) was found to be superior in efficacy and preferred by patients when compared with betamethasone valerate lotion for scalp psoriasis. This foam becomes a cosmetically elegant liquid upon contact with the skin and is well accepted by patients for psoriasis on the trunk and extremities as well as the scalp. Clobetasol propionate is now available in a foam for the treatment of body and scalp psoriasis.
Next: Topical Sequential Therapy in Psoriasis
Disclaimer
The information given in this article is for educational purpose only so that patients are aware of the options available. No diagnosis should be made or treatment undertaken without first consulting your doctor. If you do so, the author or suite101 will not be responsible for any consequences. The images provided are for illustration purpose only.
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