New Health Guide

Prickly Heat

Sep 22, 2014

Prickly heat, also known as miliaria and heat rash is not just for babies. Even though it is a common condition in infants, adults can also be affected by prickly heat especially in humid, hot weather. Prickly heat occurs when a person’s sweat ducts (pores) become blocked thus trapping perspiration under the skin. There are some types of heat rash that cause a prickly sensation.

Prickly heat normally disappears on its own. However, there are some severe forms of Prickly heat that require medical care. The best way to be relieved of the prickly heat symptoms is by preventing sweating and keeping your skin cool.

What Are the Symptoms of Prickly Heat?

Here are different symptoms of prickly heat. The symptoms can be categorized according to the type of prickly heat a person is suffering from.


Common or Uncommon

Place of Blockage


Duration Time


Miliaria Crystalline


Close to the skin surface

Also called miliaria sudamina. The rash looks like small clear spots that are present in crops.

The spots clear up after a few hours or in some cases, after a few days.

It is not itchy and can even go unnoticed.

Miliaria rubra


At the deeper part of the skin’s outer layer

You develop crops of small (a couple of millimeters in size) bumpy spots (tiny papules). The tiny spots can even resemble blisters. They appear in different body parts, but mostly where there is friction caused by clothes.

The rash can clear within a few days especially if you stop sweating and get out of a hot environment.

You may feel very itchy or a prickly sensation.

Miliaria profunda


The middle layer level of the dermis (skin).

Common in people who reside in hot climates and have had recurrence of miliaria rubra. When a person sweats, there are bigger, flesh-colored lumps that get formed on the skin.

Up to six weeks

Little itch but the person is at risk of developing heat exhaustion and fever i.e. if most of the skin’s surface has been affected.

When to See a Doctor

Prickly heat normally heals without the need of medical care. If your child or you have symptoms that have lasted longer than a couple of days, there are infection signs or the rash seems to get worse, you need to see a doctor. Some signs of infection include:

  • Increased warmth, redness, swelling and pain around the area affected.
  • The lesion is draining pus
  • Chills or a fever

What Are the Causes of Prickly Heat?

Prickly heat comes as a result of clogged sweat ducts. Instead of evaporating, perspiration is trapped in the skin and causing rash and inflammation. It is not clear why sweat ducts get clogged but there are some factors that play a role in it. They include:




Hot humid climate is conducive to miliaria.

Excessive exercise

Hard work, intense exercise or activities that cause extensive perspiration can cause prickly heat.


Newborns have sweat ducts that have not fully developed. As such, they can rapture easily and end up trapping perspiration under the skin.


When you bundle up a lot in winter or sleep with an electric blanket, you may end up with prickly heat.

Specific clothes

You can end up with prickly heat when you consistently wear clothes that do not allow normal evaporation of perspiration.

Creams or ointments

Heavy ointments or creams can block your sweat ducts.

Certain medication

There are some prescription medications that enhance the functionality of your sweat glands thus causing prickly heat. They include opiates, beta blockers and clonidine (Duraclon, Catapres and others).

What Are the Treatments for Prickly Heat?

General Measures

Prickly heat rarely requires specific treatment as it is not a serious condition. The rash normally clears up after some days. However, there are some things you should do to ease the symptoms:

  • Take a cold shower: This will soothe your skin and prevent further sweating. You can also stay in a room that is well ventilated or air-conditioned for a few hours for considerable relief. Alternatively, use a cold compress but make sure that you do not leave it on the sink for over 20 minutes.
  • Avoid humid and hot places: If you have to go outside into the heat, carry a small fun or look for shades. When you are exposed to the heat, you will sweat more and end up worsening the rash. Drink a lot of liquids when it is hot to avoid dehydration.
  • Choose loose clothes: Avoid wearing clothes made from synthetic fibers like nylon or polyester. These fibers trap heat easily.
  • Try hydrocortisone cream: This cream is effective in treating very irritated and itchy areas of your skin. However, do not use it on your face and make sure that you follow the instructions given on applying it.
  • Use calamine lotion: This lotion is readily available and helps to soothe irritated and sore skin.
  • Consider antihistamine tablets: They help control itching. However, you should consult a GP before taking antihistamines because they aren’t always suitable.

Home Remedies

  • Ice: Rub some ice cubes over the rashes to reduce inflammation. This will also ease the prickly sensation.
  • Cold water: Take a sponge or cotton cloth and soak it in cold water. Place it over the affected area until all water has been absorbed. Repeat this twice or thrice each day. This will give you instant relief.
  • Baking soda: Make a cooling compress for the dreadful and itchy prickly heat. Dilute a tablespoon of baking soda in a cup of cold water. Put a washcloth (clean) in the solution and squeeze out excess water. Apply the washcloth to the rashes. Water will help reduce inflammation while baking soda eases itching and irritation. Do this 4-5 times each day.
  • Fresh Aloe Vera: Apply the Aloe Vera leaves gel to affected regions. Leave it there for some time then take a cold bath. Use fresh Aloe Vera, though you can also use Aloe Vera gel in a pinch. Never use Aloe Vera lotions on a heat rash. Using lotions that contain Aloe Vera will only clog the pores potentially worsening the heat rash.

Check this video out for more tips on prickly heat: