Other Topical Agents
Coal tar is antiproliferative, antipruritic and can modulate inflammatory events in psoriasis. It is effective and beneficial treatment for psoriasis, particularly plaque type lesions alone or in combination with ultra violet light, as in the Goekerman regime. Crude coal tar and tar extracts such as Liquor Carbonis Detergent (LCD) has been used topically, in the form of shampoos, bath oils, creams and liquid form or may be combined with topical corticosteroids. However, its strong odor, dark colour and side-effects including acne, folliculitis and irritant/contact dermatitis limit its frequent usage. Educating the patient about its efficacy, good safety profile and its place as steroid-sparing agent increase compliance of this underutilized topical option.
Anthralin (Dithranol) has been used to treat psoriasis for over a century. Anthralin being a potent anti-inflammatory and anti-proliferative agent has been used as an adjunctive therapy for large and thick localized plaques.
It has been associated with side effects like irritation, temporary perilesional staining of the skin, and permanent staining of the clothes. “Short contact” therapy or “minute” therapy used in outpatient clinic, help to reduce side effects and improve patient compliance. It can be combined with other topical therapies or with UVB phototherapy as Ingram regimen.
Tazarotene is a retinoic acid receptor specific topical retinoid, FDA approved for treatment of psoriasis in ≥ 12 year old patients. It acts by restoring normal epidermal differentiation and proliferation and suppressing inflammation. It is available in 0.05% and 0.1% gel and cream formulations to treat mild to moderate psoriasis. Dose related skin irritation often necessitates its use as short contact, alternate day or weekend applications. Combining with topical steroids has improved its efficacy as well as tolerance. It should be preferably limited to thicker plaques, non-intertriginous sites and thicker areas such as nails.