What Causes Rashes?

by | Apr 21, 2020 | Blog, Dermatologist, Eczema, Hives, Itchy, Rash


What Causes Rashes?

Have you ever wondered what that red mark or spot is on your skin? The dreaded rash is something that we are all keen to avoid. They come in many different forms, sometimes gradually sometimes without warning. Not only do they vary greatly, their cause could range from nothing to something serious. Unfortunately, rashes are a part of our life whether we like it or not. However, it doesn’t harm us to understand their cause. 

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What Is A Rash? 

A rash is usually a red mark on the surface of the skin. They can be caused by a host of reasons and we’ll dig into that a little later. In all, a rash is a reaction to something. It could become swollen, red and even blister. Regardless, this is your body reacting to something it doesn’t like. Your body does not produce a rash because its happy! 

Genetics can also play a part in your the rashes you get. Depending on your genes you could be more sensitive to certain environmental factors, foods or otherwise. It’s also worth pointing out that ‘rash’ is not a specific diagnosis. It simply refers to any sort of inflammation or discoloration that distorts the skins normal appearance. 

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What Is Causing My Rash? 

The cause of your rash could be due to a plethora of conditions. Rashes are not easy to diagnose and in some cases even doctors struggle to diagnose correctly. We would always recommend speaking to a board-certified dermatologist if you have a persistent rash. Equally, we have created artificial intelligence that allows you to search for potential skin rash causes. Simply upload an image and we provide the results. 

To help us understand what causes rashes we’re going to split into 2: Non-infectious rashes and infectious rashes. From there you can read more about a range of rashes that could potentially affect, or be affecting you.


Non-Infectious Rashes 

These rashes are some of the most common and are caused by a variety of reasons. In some cases it could simply be due to skin hydration, others it could be an allergy. Either way these rashes are non infectious rashes – they aren’t viral, fungal, bacterial or parasitic. 

Most non-infectious rashes are a form of dermatitis but there are other conditions such as hives (urticaria) which could be caused by an allergy. Remember we’re only really scratching the surface here so if you’re unable to see a rash that matches your condition, remember to speak to our dermatologists. 

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Infectious Rashes 

We’re going to split these rashes into 4. Bacterial, Fungal, Parasitic and Viral. 

Bacterial Rashes

Eruptions caused by bacteria tend to be postular (small bumps filled with pus) or could be plaque-like and painful. Here’s some of the most common for you to read up on: 


Fungal Rashes

Fungal infections can be quite common and usually appear as fiery red marks with pustules (blisters) around the edges. Normally they affect folds in the skin such as the groin or breast area. Here’s some of the most common fungal rashes to look out for: 


Parasitic Rashes

These rashes are usually caused by some kind of mite. Typically contracted by prolonged contact with an infected individual. It does not produce symptoms until the host becomes allergic to the mites after around 3 weeks. The most common: 


Viral Rashes – Exanthem

Viral rashes are known as exanthems. Usually they are symmetrical and affect the skin surface all over the body. There are even arguments to suggest Covid-19 can cause reactions on the skin. Occasionally they are caused by STDs and may come with other symptoms such as coughing and sneezing. Here are the most common: 

As you can see, there are many forms of rashes with many causes. This is precisely why we recommend speaking to a dermatologist if symptoms persist. Rashes can be very uncomfortable but are almost always treatable. If combing through our skin guide is too much for you, give our artificial intelligence a try. It will provide 5 answers with 80% accuracy – this will help you refine your search! 

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