Prickly heat, the blight of many during Hong Kong's hot humid summers, is an itchy rash characterised by small raised red spots that cause an itchy and/or intense prickly sensation on the skin. It can develop anywhere on the body but is more commonly found on the creases in the skin such as on the neck, armpit, groin, thighs. The body regulates excess heat by sweating: the evaporation of sweat from the skin's surface has a cooling effect. Dead skin cells and bacteria often accumulate in the sweat glands during the process. Prickly heat develops when the sweat ducts become blocked and the sweat can't escape. Instead, it seeps into nearby skin tissue causing small pockets of inflammation which appear as a rash. Gianna Buonocore, Traditional Chinese Medicine (TCM) practitioner at the Integrated Medicine Institute, Central says: 'The condition often occurs during the summer months, when sweat is trapped in the pores. These hot skin rashes may be accompanied with low grade fever and a yellow sticky coating on the tongue.' Mint is supposed to help bring the rash to the surface and is thought to benefit itchy rashes in general and is widely used for this in TCM.