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Heat Rash - Causes, Symptoms, Risk Factors, Diagnosis and Treatment

Published on May 03, 2022 and last reviewed on Nov 24, 2022   -  5 min read


Heat rash is a common condition for children and adults, especially during hot, humid weather. Read this article to know more about this condition.


What Is Heat Rash?

Heat rash, also called prickly heat and miliaria, is a common skin condition mainly affecting children and adults in hot, humid weather conditions. Heat rash develops when the blocked pores trap sweat under the skin. Heat rash often affects the areas where sweating is more likely to happen, including the face, neck, under the breasts, under the scrotum, in folds of the skin, and areas where skin rubs together or against clothes, including the back, chest, and stomach. Heat rash can be concerning, uncomfortable, or itchy; it is not dangerous. It usually clears on its own once the skin cools off.

What Are the Symptoms of Heat Rash?

Symptoms of heat rash

The symptoms of heat rash are similar in both children and adults, and they last about two to three days. The common symptoms of heat rash include:

What Are the Main Causes of Heat Rash?

Causes of heat rash

Heat rash typically develops due to a blockage and inflammation of sweat ducts in hot, humid conditions. It is not clear why the sweat ducts become blocked, but certain factors contribute to it, including:

What Are the Risk Factors of Heat Rash?

The factors that make a person more prone to heat rash include:

How Is Heat Rash Diagnosed?

No tests are required to diagnose heat rash. The diagnosis of heat rash is based on a physical examination. The doctor examines the rash, possibly using a dermoscopy for a closer inspection. If needed, the doctor may also recommend a skin punch biopsy to detect the cause of the rash.

When to See a Doctor?

Heat rashes are often harmless. They usually heal without problems. But if the symptoms do not resolve in a few days, the heat rashes can become worse and can also lead to bacterial infection, causing inflamed and itchy pustules. See a healthcare provider if a person with heat rash notices the following signs of infection, such as:

How Is Heat Rash Treated?

Avoiding overheating is the best way to treat mild heat rash. Once the skin is cool, the heat rash clears up quickly. However, the doctor may recommend over-the-counter or prescription medications to treat moderate to severe forms of heat rash, including:

Pharmacological Treatments:

1. Ointments

Ointments may help relieve discomfort and prevent complications. Various ointments are available to manage the symptoms of heat rash, such as:

2. Over-the-Counter Antihistamines

Topical or oral antihistamines can relieve the itching associated with heat rash. Consult a pediatrician about which type of antihistamine is better for a child.

3. Lifestyle and Home Remedies

A few tips that can help heal heat rash and soothe the skin include the following:

How to Prevent Heat Rash?

The most effective way to avoid heat rash is to stay away from situations that cause excessive sweating. Try the following tips to protect the skin from heat rash:


Heat rash is a common skin problem, especially in a hot, humid climate. The condition usually goes away without treatment, although home remedies can help soothe the rash and relieve the discomfort. If heat rash persists for more than a few days, seek medical attention. Since heat rash occurs when the body overheats and sweats, it can be prevented by keeping the skin cool.


Frequently Asked Questions


How to Get Rid of Heat Rashes?

Avoiding heat exposure is the best way to treat mild heat rash. Once the skin is cool, the heat rash clears up quickly. Over-the-counter or prescription medications, including calamine lotion, topical steroids, and antihistamines are used to treat moderate to severe forms of heat rash.


What Does a Heat Rash Look Like?

The symptoms of heat rash are similar in both children and adults. A heat rash looks like tiny red bumps or spots on the skin (papules). There may be itching or prickling sensation due to inflammation of the outermost layers of the skin (epidermis) and mild swelling of the affected area. Inflammation and infection can occur if bacteria enter the clogged sweat glands.


How Long Does a Heat Rash Last?

On average, heat rashes last for two to three days. Heat rashes usually disappear on their own within two to three days as long as the affected area is not irritated further. Mild heat rashes can resolve within a few hours or days. Severe forms of heat rashes may persist for weeks.


Is It Possible to Get Rid of a Heat Rash Overnight?

Yes, mild heat rashes can resolve within a few hours or days with simple home remedies such as taking cool showers, using a gentle soap, letting the skin air-dry instead of toweling off, and using calamine lotion and cool compresses.


What Is the Best Cream to Put on a Heat Rash?

Hydrocortisone cream (1 %), a type of corticosteroid, available without a prescription is the best cream to help relieve symptoms of heat rash. It should be applied once or twice a day to soothe itching from a heat rash.


Who Can Get a Heat Rash Easily?

Heat rashes are more common in newborns, obese people, and the elderly. People living in hot, humid climates, with limited mobility, and those who do vigorous exercise, hard work, or any physical activity that causes profuse sweating are at a greater risk of developing heat rashes frequently.


How Are Heat Rashes Prevented?

To prevent heat rashes, stay away from situations that cause excessive sweating. On hotter days, wear lightweight clothes made of natural fibers, stay in cool and well-ventilated areas, use air conditioners and fans, take cool showers or baths, use ointment or cream to keep the skin moist, and avoid scratching the skin.


What Are the Clinical Features of a COVID Rash?

COVID rashes are typically discolored as compared to the neighboring skin. On light-skinned people, rashes may appear red, pink, or purple, while on dark skin, these look purple, ashy gray, or dark brown. The affected site may appear swollen or puffy in comparison to the surrounding skin. Some COVID-19 rashes may be itchy.


How Long Do Heat Rashes Last on Babies?

Heat rash is a common problem in babies. They usually go away on their own within three to four days as long as the affected site is not irritated further.

Last reviewed at:
24 Nov 2022  -  5 min read




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