Heat rash can be caused by high temperatures and doesn’t always involve the sun. However, sun poisoning is directly caused by excessive sun exposure.

If you spend too much time in the sun without protection, you may end up with sore and red skin. This is caused by the UV rays that the sun emits and can even lead to sun poisoning. However, it’s essential to note that there are differences between heat rash vs sun poisoning, even though the names might be used interchangeably. This article aims to explain these differences and help you understand how to treat each condition.

Understanding Sun Poisoning and a Heat Rash

In comparing heat rash vs sun poisoning, we will first discuss each condition before examining their differences.

Sun poisoning is generally considered a painful condition. When you reach this level of sunburn, the pain may spread throughout your entire body. On the other hand, a heat rash is usually more localized to specific areas. While a heat rash can come with some pain, people often complain more about the irritation and itchiness that it causes.

There are some areas where sunburn and a heat rash collide. For example, extended exposure to the sun causes a heat rash to develop as in the case of hell’s itch sunburn.

Possible Causes for a Heat Rash

Let’s begin by discussing a heat rash. This is a type of rash that typically occurs due to the combination of heat and friction, and is not solely caused by sun exposure. If you’re asking, “Why do I itch when I get hot?” – then it’s likely due to this type of rash. Let’s take a closer look at the possible causes in more detail:

  • Hot and humid weather: Warm, humid weather tends to be the most common reason for heat rashes. You don’t necessarily have to be out in the sun. Sweating when indoors can result in a reaction by your skin[1] – causing you to develop this rash.
  • Physical activity: When you exercise, your body’s core temperature increases[2], and you begin to sweat. The combination of these two elements can contribute to heat rashes.
  • Synthetic or tight clothing: Certain fabrics, especially if they sit tight on your skin, can cause friction. It’s important to understand that this friction generates some heat and can damage your skin or a rash can sometimes develop.
  • Overheating: When you get too hot, you may start noticing the development of a heat rash.

What Symptoms will Heat Rash Cause?

Some symptoms can occur if you develop a heat rash. Knowing what these symptoms are can help you differentiate between a heat rash and other conditions like sun poisoning.

Here are some of the most common symptoms linked to a heat rash:

  • The area affected by the heat rash will have a reddish color.
  • Small blisters will likely develop. The blisters will look like small bumps on your skin.
  • You’ll notice that the area becomes itchy, and you may have urges to scratch the blistering skin.
  • Some people also complain about a prickly feeling on the affected skin.

Heat Rash Treatment Options

There are several ways to treat a heat rash, but it’s crucial to understand why it occurs. By doing so, you can take preventive measures to avoid its recurrence in the future.

  • The first step is to get a damp cloth that you ran under the cold water tap and place it on the rash.
  • You can also take a cold bath or shower, as that can be quite soothing for the rash.
  • Allow your skin to air dry. Using a towel could make the rash worse.
  • Some people may find that a hydrocortisone cream helps to get rid of the rash faster.
  • If you’re asking how to get rid of heat rash quickly, you might also want to consider an antihistamine.

Some people may wonder, “Does heat rash spread?” The good news is that it’s generally not caused by a virus or other microorganism that could make it contagious.

Sun Poisoning Overview

In this comparison of heat rash vs sun poisoning, the latter is the more dangerous one. Sun poisoning is a more severe form of sunburn.

In most cases, sun poisoning will be very painful. You may also notice classic symptoms of sunburn, like redness, and itching, and your skin can start to peel after a few days.

The Symptoms of Sun Poisoning

It’s important to understand how you can identify sun poisoning. Remember that it’s the same as sunburn, but more severe. You’ll also be able to know when to worry about a rash in adults by understanding these symptoms.

Let’s take a look at some signs and symptoms of sun poisoning:

  • Moderate to severe pain
  • A tingling sensation in your skin
  • Redness, often accompanied by blistering
  • Dizziness
  • Nausea
  • Fever or chills
  • Headaches
  • Swelling of your skin

Dehydration is also a relatively common issue that people face when they have sun poisoning.

Sun Poisoning Causes and Risk Factors

The main cause of sun poisoning is excessive sun exposure. It usually happens when you spend too much time in the sun. Your risk is much higher when you decide to spend time in the sun between 10 am in the morning and 4 pm in the afternoon. This time is generally considered the peak time for the sun.

Sun Poisoning Causes

Prevention Strategies for Sun Poisoning

It’s possible to avoid getting sun poisoning. Let’s take a closer look at the strategies that can help protect you.

  • Apply and reapply sunscreen: Use a high-quality and high-SPF sunscreen. Apply it in the morning and carry the bottle with you – that way, you can reapply the sunscreen[3] regularly to keep your skin protected during the day.
  • >Wear a wide-brimmed hat: Consider using a hat to help provide shade for your face whenever you go outside.
  • Wear protective clothing: You can also wear clothing that helps to prevent UV rays from reaching your skin. Similarly, you don’t want these clothing pieces to sit too tight on your skin.
  • Take breaks in the shade or indoors: If you spend a lot of time outside, make sure you take measures to get out of the sun now and then. You could search for some shade in the area or go indoors for a while.
  • Avoid the sun during peak sun hours: The UV rays of the sun are generally at their most dangerous from 10 am up to 4 pm. Limit how much time you spend in the sun during this time.
  • Stay hydrated: Sunburn can make you dehydrated, and if you’re already dehydrated, the UV rays from the sun may be even harsher on your skin. Drink enough water to keep yourself (including your skin) hydrated.
  • Moisturize: Another important tip is to use a moisturizer. You can use this alongside your sunscreen. The moisturizer helps to prevent skin dryness and can also add an extra layer of protection. An option like the Infusoderm Deep Hydration Daily Moisturizer can be a great choice.

Treatment Options for Sun Poisoning

If you already have sun poisoning, then you have to make sure you know how to treat the condition. There are a couple of treatment options, so let’s look at a few:

  • Limit sun exposure: You first need to reduce the amount of time you spend in the sun. Since you already have sun poisoning, focus now on recovery instead of making the issue worse.
  • Use cool compresses: To help you find some relief in the symptoms that sun poisoning causes, consider applying a cool compress on your skin.
  • Take cool baths or showers: You’ll also notice that taking cool baths or showers helps relieve the hot feeling and dryness of the skin.
  • Avoid scratching or peeling the affected skin: Don’t scratch your skin – that’s going to burst the blisters, make the condition more painful, and even leave marks behind.

Differentiating Heat Rash & Sun Poisoning

When you compare heat rash vs sun poisoning, it’s important to understand the main differences. Heat rash can be caused by high temperatures and doesn’t always involve the sun. However, sun poisoning is directly caused by excessive sun exposure.

If you have small areas of your skin that feature a red rash with blisters, then it’s likely a heat rash. However, if you have pain over your entire body and you notice severe redness and blistering, then these symptoms could be a sign of sun poisoning.


Is heat rash the same as sun rash?

There are similarities between the two. However, if you have a heat rash, you may also notice small bumps develop on your skin. These bumps are itchy and filled with a clear fluid.

What are the two main signs of heat rash?

Redness and small blisters are usually the main symptoms that you’ll get when you have a heat rash. However, other things also signal this type of rash, such as itchiness.

How long do heat rashes last?

In most cases, the rash will clear up about two to three days after it develops. If you scratch the blisters or do not follow proper self-care techniques, then it may take longer to completely heal.

Can too much sun make you sick?

When you are exposed to the sun for too long, you can develop sun poisoning which can sometimes be dangerous.

Does sunscreen prevent sun poisoning?

While sunscreen can help prevent sunburn, it’s important to understand its limitations. Re-applying sunscreen regularly can help, but you also have to consider the temperature and level of UV exposure.


Heat rashes are quite common and can happen for several reasons. However, when it comes to sun exposure, it’s important to be mindful of sun poisoning, a condition that may sometimes require medical intervention. It’s important to understand the differences when comparing heat rash vs sun poisoning, as the symptoms can differ and also tend to be more dangerous, as we explained in this article.