Introduction
Topical steroids are anti-inflammatory agents used for the treatment of steroid responsive skin disorders. Treatment of skin diseases was revolutionized with the advent of these anti-inflammatory corticosteroids.
Mechanism of Action
The mechanism of the skin-lightening effect of topical corticosteroids is ill-understood. Melanocytes respond to a wide variety of chemical mediators. The inhibitory effects of corticosteroids on the synthesis of mediators like prostaglandin and leukotriene may partly explain their effects on melanogenesis.
Formulations
Topical steroids are used in combination products for their synergistic effects and for the reduction of irritation from other products like tretinoin. Various combinations with HQ and retinoic acid have given good cosmetic results in clinical trials.
Topical steroids are divided into four groups according to their potency in keeping with the British National Formulary (BNF), while the American system classifies them into seven classes, with class 1 corresponding to the very potent, superpotent or ultrahigh potency. Class- 1 topical steroids are very potent, e.g., clobetasol propionate,' and local side effects are most commonly seen with prolonged usage (>3 weeks), particularly on areas of skin such as the face or flexures.
Steroid Safety
Potent or superpotent steroids, when used alone, have been associated with good therapeutic responses, but monotherapy is not recommended due to their frequent untoward effects. For example reversible hypopigmentation of normal skin is a well-known untoward effect of prolonged potent steroid application.
Documented side effects from studys provide the following statistics:
A study shows that motives for hospital visits to the skin clinic were, chiefly, patchy darkening of the face. This was the chief presenting complaint in 201 (36.7%) cases, followed by widespread itchiness/irritation of the body or face/± the intertriginous areas in 147 (26.9%), bizarre rashes in 138 (25.2%), while 61 (11.2%) had multiple complaints.
Skin disorders documented during dermatologic/systemic examination included widespread dermatophyte infections with lesions that were often atypical appearing, and diagnosis was frequently delayed or missed. These were found on various parts of the body in 191 (34.9%) individuals.
Macular hyperpigmentation of the face occurred in 204 (37.3%) cases. Acne vulgaris occurred in 248 (45.3%) cases, and these were seriously inflamed with huge pustules and micropapular eruption over the entire face. Pityriasis versicolor was also widespread and located in unusual sites such as the medial aspects of both upper and lower limbs in 31 (5.7%) patients. These were deeply depigmented and associated with superficial atrophy. Of these, three patients also had associated diabetes mellitus, which was of recent onset. Other disorders/complications noted were widespread striae in 161 (28.3%) telangiectasia in 117 (21.3%); easy bruisability was noted in 95 (17.4%) and hypertrichosis in 73 (13.3%) cases.
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