Don’t scratch that itch How to deal with contact dermatitis By Mark Wong Have you ever developed a rash, followed by reddening, swelling and itching after coming into contact with certain substances? You may have had contact dermatitis, an inflammatory response of the skin to an environmental irritant or allergen. Any part of the body may be affected, although the most common areas are the hands.    What causes it Contact dermatitis triggers include chemical substances such as acids, alkalis or detergents, adhesives from plasters, cosmetics, certain plants, costume jewellery or rubber materials. Diaper rash, which is common in babies and incontinent adults, is also a form of contact dermatitis, in which trapped urine and faeces irritate the skin. In most cases, identifying the source of the condition and removing it suffices to relieve the condition.   Contact dermatitis can be treated with the following topical medications:    •   Steroid creams        They come in different strengths and help relieve itch and inflammation. You may obtain low-        strength steroid creams such as hydrocortisone (1% or 0.5%) from your pharmacist. If a low-        potency steroid fails to work, stronger steroids such as betamethasone or clobetasol may        be required. These are available only with a prescription. Steroids are usually taken twice        daily and should be used sparingly for no longer than five to seven days. Prolonged use of        topical steroids may result in skin thinning and make the area prone to infection.     •   Non-steroidal creams        These include ichytmmol or cromatition, which may help in itch-relief.    •   Calamine lotion or colloidal oatmeal preparations        These are effective for large itchy areas.   If the rash becomes weeping and exudative (when liquid or pus oozes out), a secondary bacterial infection may have set in and you should consult your doctor. If sedation is required, an oral antihistamine such as chlorpheniramine may be given at bedtime.   Preventive measures Still, long-term use of medication is not the answer to eliminating contact dermatitis. If avoidance of irritants or allergens is not practical for occupational reasons for example, prevention is the key.  1.   Use vinyl gloves when dealing with chemicals or soaps. Make sure that the gloves do not       contain holes or they may trap chemicals and make the condition worse.  2.   Apply barrier creams containing dimethicone or silicone if contact with allergens or irritants is       expected. Alternatively, apply emollients or moisturisers to strengthen the skin’s natural       barrier function.  3.   Use soap and fragrance-free cleansers when washing the affected area. Take note to use       proper skin cleansers, not industrial solvents or detergents.      A mild soap should be adequate for office work, while a non-aqueous cleanser may be needed to remove grease and oil.