Prickly heat, heat rash or summer rash is caused by sweat blocking the epidermis. It causes an itching or burning sensation, and often little blisters or deeper red lumps are visible on the surface of the skin. It is not contagious, and it has no connection to skin cancer or malignant melanoma.
It can affect anyone at any age, but is most common in women between the ages of 20-40 with lighter skin tones. It is thought that 10% of the population experience heat rash or photosensitivity, and that well over half the population experience some level of itching, skin prickling or discomfort when they are exposed to sunlight.
Miliaria Crystalline: A mild form of prickly heat causing small bubbles on the skin about 1-2mm in size, usually without skin redness or pain and itching. Forming when sweat ducts get clogged in the upper most layer of the skin, this type of heat rash is common in new babies, but can occur in adults where it usually appears on the forehead, neck, back and chest.
Miliaria Rubra: Characterised by an itchy and prickly sensation and red bumps on the skin, this heat rash affects the middle layers of the skin. It can occur in adults exposed to heat and humidity and also in babies of up to three or four weeks of age.
Miliaria Profunda: An uncommon form of heat rash that usually occurs in adults who have recurring Miliaria Rubra. It affects the deeper layers of the skin and can cause flesh coloured skin lesions around 1-3mm in size on the body, arms and legs. Sufferers may also experience nausea, increased pulse rate and dizziness.
Polymorphic Light Eruption (PMLE): Often occurring at the first signs of sun in the spring, or in the first couple of days on a holiday in a new climate, Polymorphic light eruption (PMLE) is a skin rash that occurs as a result of exposure to the sun. It is not harmful or contagious, but it can be uncomfortable and embarrassing.
Prickly heat usually affects parts of the body covered by clothes, such as the back, abdomen, neck, upper chest, groin or underarms.
Predominantly caused by exposure to sun, heat and humidity, Prickly heat can be also be triggered by any number of reasons including: