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Heat bumps on the skin, also known as heat rash, usually develop from excessive exposure to heat or humidity. The condition may be as mild as a few small bumps but can also develop into painful blistering of the skin. According to the Centers for Disease Control and Prevention, heat rash is one type of heat stress, in which your body becomes overheated and is unable to properly cool itself.

Why Heat Bumps Develop

Heat bumps are a result of clogged sweat ducts. When your body's temperature rises, it will naturally try to cool itself by sweating. If your skin remains wet from the sweat for long periods of time, the sweat can seep into sweat ducts, causing them to become clogged and inflamed.

Where Heat Bumps Form

Heat bumps can develop anywhere on your body. Some of the more common places they form are areas where skin-to-skin contact is constant, such as under your breasts, or where air flow is restricted, such as the groin. Other common areas likely to develop heat bumps are the chest and in the skin folds on the neck.

How to Treat Heat Bumps

If you develop heat bumps, keep the skin as dry as possible to keep the rash from getting worse or becoming infected. Avoid friction on the skin, which can occur with tight-fitting clothing. If the rash is in a place where air flow is minimal, try using baby powder to absorb excess moisture. If heat is unavoidable due to work or other situations, take frequent breaks and give your body a chance to cool down. If your bumps are blistery, avoid breaking them open, which can cause infection.

High Risks

Those who work in hot environments, such as construction workers during the summer months, and firefighters and others who are frequently exposed to high-temperature working conditions are highly susceptible to heat bumps. Additionally, people whose bodies are weaker -- such as babies, children and the elderly -- are at a higher risk of heat bumps and other related heat stress symptoms.

Additional Causes

Hot weather isn’t the only thing that can cause you to become too hot and develop heat bumps. In colder conditions you may tend to over-bundle yourself or your children to stay warm, which can increase sweating and decrease air flow to the skin. Your body temperature is also higher when you have a fever, but extremely high fevers can cause heat rash due to the fact your body is trying to cool itself by sweating.