Prickly Heat

Also known as "miliaria rubra", prickly heat is a type of miliaria (sweat rash) characterised by red, blister like eruptions (called papules). It is caused by sweat glands becoming blocked and inflamed due to excessive sweating.  This in turn causes the sweat to leak into the deeper layers of the epidermis. There are several types of miliaria, from the mildest to the most severe;

• Miliaria crystalline  - Also known as sudamina is the mildest form of miliaria, this is caused by blockage of the sweat glands close to the surface of the skin & is characterised by tiny, clear papules that rupture easily.

• Miliaria rubra (prickly heat) - The most common form. Characterised by red papules, itching and a sensation of pins & needles on the skin.

• Miliaria profunda - The least common, but most severe form of miliaria in which the sweat leaks into the deeper layers of the dermoepidermal junction.

• Miliaria pustulosa - A complication of miliaria rubra where the papules become infected and form pustules (pus filled pimples).

Prickly heat is more common in the summer months. People of any age can become affected although it is more common in children and especially infants due to their under-developed sweat glands.

How does prickly heat occur?

Heat rash can occur from a variety of reasons, basically anything that can cause sweating can lead to heat rash. Common causes include;

• Sun exposure.

• Sun bed use.

• Exposure to heat and humidity.

Symptoms of prickly heat:

• Tiny red papules (bumps). These can occur on any part of the body, but commonly affected areas prone to sweating or in the skin folds. Common areas include; underarms, neck, back, shoulders, chest & the nappy area on infants.

• Affected areas will not produce sweat.

• Itching & or the sensation of tiny needles pricking the skin (hence the name).

Prickly heat treatment:

Fortunately, prickly heat is self limiting & usually resolves itself within 24-48 hours. Treatment is aimed at relieving symptoms & may include;

• Application of a cold compress to the affected area can offer relief.

• Oatmeal  baths or calamine lotion to relieve itching. Make sure the water is lukewarm.

• Keep the skin dry and cool. Stay indoors in the air conditioning if possible.

• Avoid excessive rubbing of the skin, wear loose clothing.

• Topical steroid cream if the above methods don't offer relief. Ointment should be avoided as it can further block the pores.

Please note:

The medical articles on this site have not been written by a doctor & should not be considered a replacement for a doctor visit. The articles are provided for informative purposes only.

Always seek immediate medical advice for any problems.

While great care has been made in the creation of these articles, we cannot guarantee the accuracy or omissions on these pages. If in any doubt whatsoever, seek professional medical advice.