Heat Rash: Types and Symptoms, Causes, and First Aid Management

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Heat rash is not an uncommon skin condition wherein there is intense itching of the skin that often feels stinging or prickly. It also commonly called miliaria, sweat rash or prickly heat. Heat rash occurs when a person sweats excessively and blocks one of the sweat glands, thus perspiration is trapped under the skin. This results to tiny red bumps in a region of red skin. These bumps usually appear on the clothed area of the body such as the upper chest, abdomen, back, neck, armpits, or groin.

Heat rashes usually resolve on their own. However, in severe cases, they may develop into heat cramps, the first of a three-part spectrum of heat-related illnesses, which can progress further to heat exhaustion and finally heatstroke, a serious condition and is considered a medical emergency.Similar to the heat-related illnesses, heat rash is more common in hot, humid conditions. Although it is most common in infants, it can occur to any one at any age.

Types and Symptoms of Heat Rash

There are three types of heat rash, each varied by their symptoms and location in the skin. Infants may not always be verbal about their symptoms so it is best to watch out for any of the following:

  • Miliaria crystallina
    • Mildest form
    • Affects the top layer of the epidermis only
    • Symptoms: clear, fluid-filled blisters and bumps that easily break that are not usually itchy
  • Miliaria rubra
    • Also called prickly heat
    • Occurs deeper in the epidermis
    • Symptoms: red bumps that are itchy or prickly in the affected region with little or no sweating
  • Miliaria profunda
    • More common in adults with repeated spells of miliaria rubra
    • Affects the dermis, the deeper layer of the skin
    • Symptoms: firm, fresh-coloured gashes that apply soon after completing an activity but there is little or no sweating

What Causes Heat Rash?

It is not always known why the sweat ducts become clogged, but several factors are said to influence the blocking of the ducts.

  • Tropical climates
  • Immature sweat ducts, particularly in newborns
  • Strenuous physical activity that leads to extensive sweating
  • Wearing too much clothes or too thick clothes
  • Particular fabrics
  • Medications
  • Heavy creams and ointments
  • Prolonged stay in the bed, especially if with fever

How is Heat Rash Given First Aid Treatment?

Heat Rash
Heat Rash

Heat rash can be treated at home to relieve of symptoms and reduce discomfort. It does not usually require medical treatment, except in severe cases.

  • Avoid sweating. If possible, stay in air-conditioned rooms. If this is not possible, stay in rooms with well-circulated air.
  • Avoid wearing thick clothes, but rather, wear lightweight clothes.
  • In cases of itching, calamine lotion may be applied topically to relieve of itching.
  • To prevent the glands from clogging, anhydrous lanolin may be applied topically.
  • In severe cases, topical steroid may also be applied.

Disclaimer: This article should not serve as substitute for medical advice nor medical treatment. It is highly recommended for parents and caregivers to join in Standard Childcare First Aid Courses to learn to apply first aid in cases where it might be necessary, such as in heat rash.

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