Conditions & Treatments

Prickly Heat

Prickly heat is a skin rash caused by trapped sweat under the skin.

Prickly Heat

What is prickly heat?

Prickly heat, also called miliaria, is a skin rash caused by trapped sweat under the skin. Sweat can become trapped when the narrow ducts through which sweat travels to the surface become clogged. Prickly heat tends to be more common in warmer, more humid climates. The condition usually appears on the torso and thighs, especially where skin touches skin.

What are the symptoms of prickly heat?

The following are the most common symptoms of prickly heat. However, each individual may experience symptoms differently. Symptoms may include:

  • Itching

  • Irritation (prickling)

  • Small blisters

  • Large, red areas on skin

The symptoms of prickly heat may resemble other skin conditions. Always consult your doctor for a diagnosis.

Treatment for prickly heat

The condition usually clears up when sweating is avoided. Other treatment may include:

  • Keeping the skin cool and dry

  • Corticosteroid lotions

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