Burns are classified according to their cause - thermal burns are caused by flames, hot oil, steam, and hot objects like irons and stovetop burners; scalding is due to boiling or hot water or other liquids; chemical burns are due to exposure to acids and alkali (drain and oven cleaners, strong bleach); electrical burns are from touching ‘live’ electrical sources - and according to the severity of tissue damage. A first-degree burn causes superficial redness and swelling, and usually heals in 3-5 days with little or no scarring; a second-degree burn has redness, swelling and blistering, extends deeper, affecting sweat glands and hair follicles, and takes around 7-10 days to heal - and can leave some scarring; a third-degree burn, or ‘full-thickness burn’, causes damage down to and including the fatty subcutaneous tissue layer, and also muscles and bone. This has a high risk of infection, and skin grafts are required.

What doctors tell you Only first- and minor second-degree burns are considered self-treatable. Severe second- and third-degree burns require medical attention as they lead to a greater risk of complications such as skin and systemic infections, fluid loss and shock. Electrical and chemical burns should also be seen to in a hospital.

Minor burns are usually treated with topical antimicrobial creams, the standard being silver sulphadiazine cream. Applied to the affected areas, it prevents and treats the bacterial or fungal infections that may occur.

Reported adverse skin reactions to silver sulphadiazine include hypersensitivity reactions, allergic contact dermatitis and erythema multiforme (where the skin erupts into symmetrical, circular, raised lesions). With prolonged and excessive use, the silver can be absorbed through the wound and deposited in large amounts throughout the body, including the skin, labial mucosa, gums, kidneys, liver and cornea (Clin Chem, 1995; 41: 87- 91; Ann Dermatol Venereol, 2002; 129: 217-9). The result is ‘argyria’, where the skin has a bluish-grey appearance, and there is organ dysfunction due to silver toxicity (J Am Acad Dermatol, 2003; 49: 730-2; Burns Incl Therm Inj, 1985; 11: 197-201; Burns, 1992; 18: 179-84).

Tina Tan