What is skin rash?

Healthcare provider talking to a patient who is sitting on the exam room bed – maybe about a skin rash

Our skin has many jobs. Not only does it work to stop our bodies from dehydrating, it also helps regulate our temperature and can protect our joints from bumps and small injuries.

The skin is also a good indicator of our health too and any changes in its appearance can signal something isn’t right. Skin rashes, for example occur when the texture, color, and temperature of the skin has changed. This can happen for many reasons, such as allergy or infection.

The treatment you receive for skin rash depends on the cause. Rashes caused by minor allergies for example can be treated with over-the-counter antihistamines.  If your rash is taking a while to go away and is feeling itchy, your Healthcare provider may suggest a lotion to soothe the skin as it heals.

Causes of skin rashes

Allergies, autoimmune conditions and infections can all cause skin rashes. During a skin rash diagnosis, additional symptoms are also considered, such as sore throat and headache.  If your skin rash is a suspected allergic reaction a Healthcare provider may also ask what you were doing before it developed.


Contact allergies, including allergic contact dermatitis, usually cause skin rashes. This happens when the body reacts to an allergen touching your skin. With contact allergies the rash may take a few days to appear. Other things people can be allergic to and get a rash from include food, insect venom and latex.

How many allergy
types are there?

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People can also experience skin rashes when taking medications, for example penicillin. When this happens a person could have drug allergy. Drug allergy can sometimes cause anaphylaxis, which is a life-threatening reaction to an allergen that affects your whole body (systemic). Hives can be a symptom of anaphylaxis, it usually develops almost immediately and presents with other symptoms, for example shortness of breath.

Symptoms of anaphylaxis include:

  • Flushed or pale skin, that may feel itchy with hives
  • Diarrhea, feeling or being sick
  • Low blood pressure (hypotension)
  • Swelling of the tongue or throat
  • Weak and rapid pulse
  • Airways tightening, which may cause wheezing and trouble breathing
  • Dizziness or fainting

Go straight to information about the treatment for anaphylaxis and what to do if you experience the symptoms.

Autoimmune conditions

An autoimmune condition occurs when your immune system begins to attack your body. An example of this is lupus. One telling symptom of lupus is a malar rash (named after the Latin for jawbone). This type of rash develops on the cheeks and bridge of the nose and is very common in children with lupus. It’s also known as butterfly rash due to its distinctive shape.


You could develop skin rash from the following infections,

Wasp stinger – the insect uses it to inject venom which can cause an allergic reaction

Insect sting allergy
can cause a rash

Bacterial infections

Examples of bacterial infections that cause skin rash include:

  • Cellulitis
  • Impetigo
  • Scarlet fever

Viral infections

Examples of viral infections that cause skin rash include:

  • Chicken pox
  • Hand, foot and mouth disease
  • Slapped cheek syndrome

Fungal infections

Examples of fungal infections that cause skin rash include:

  • Candidiasis
  • Ringworm
  • Athlete’s foot

Examples of common skin rashes and their treatments

Most of these rashes are caused by allergies, infection and autoimmune conditions, and include:

Contact dermatitis rash

There are two types of contact dermatitis, one is irritant and the other is allergic:

  • Irritant contact dermatitis: A rash develops when something irritates the skin, for example soap. The immune system is not activated.
  • Allergic contact dermatitis: When an allergen touches the skin, this activates the immune system, causing inflammation and a rash. Examples of allergens could be poison ivy, latex or even nickel in coins. Also some airborne weed pollens.

Allergy treatment

A young boy on his father’s shoulders, with his smiling mum looking up at him, surrounded by birch trees

Symptoms of contact dermatitis include:

  • Rash and itch
  • On paler skin types the rash may look red, darker skin types may have areas of deep brown or purple skin (hyperpigmentation) or ashen grey (hypopigmentation)
  • Swelling
  • Bumps or blisters, sometimes filled with clear fluid
  • Skin can thicken


Usually a Healthcare provider would talk you through avoidance strategies, or ways you can reduce your exposure to the allergen or irritant. They may then suggest different treatment options or actions, such as:  

  • Avoiding friction to help the skin heal, for example wearing loose fitting clothes
  • Taking antihistamines to help reduce symptoms such as itching
  • Applying corticosteroid creams and lotions to the rash, but not on thin delicate skin, such as the face
  • Using emollients to rehydrate the skin and prevent cracking

Hives rash (urticaria)

Hives can develop when you experience an allergic reaction to something. For example, food, latex, and medicine – even grass. Sometimes a hives rash can feel warm, when this happens it could be a sign of heat bumps or cholinergic urticaria. This can be brought on by anything that raises your body temperature enough for you to sweat, for example exercising.

Symptoms of hives can include:

  • Raised bumps or allergy bumps
  • Swelling
  • Hyperpigmented skin: Rash appears darker than the rest of the skin but can have a lighter patch in the center; on darker skin the bumps may be the same color as the surrounding skin
  • Itchy stinging or burning feeling around the affected area
Woman at home in a camisole top, hugging her stomach with a look of pain on her face. It could be food allergy symptoms

Hives and other food
allergy symptoms


Treatment for hives depends on the cause. If it's allergy, antihistamines usually help when you can't avoid your allergen. During a particularly severe flare that is affecting several areas of the body, corticosteroids can be effective at reducing inflammation.

Sometimes hives are also a symptom of a life-threatening allergic reaction, anaphylaxis. In this instance a person would need urgent medical treatment and must go to the emergency room. Some people may have an epinephrine autoinjector on them, especially if they've been diagnosed with allergy, so always check for this.

Drug allergy rash

You can experience an allergic reaction to any drug, be it over-the-counter, prescription, or a herbal remedy.  Allergic reactions to drugs are less likely to occur than drug side effects.  

The appearance of drug rash differs depending on how your body has reacted. For example, some people develop hives, whereas others may have allergic contact dermatitis symptoms.  

Symptoms range from mild to severe and can include:

  • Itching
  • Fever
  • Swelling
  • Shortness of breath
  • Wheezing
  • Anaphylaxis
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In mild reactions, symptoms should disappear when you stop taking the drug. If, however, your skin rash is taking a long time to go away on its own, or is very itchy, topical corticosteroids could help. For severe drug allergy rash other treatments may be necessary.

Heat rash (also known as prickly heat and miliaria rubra)

When the sweat glands become blocked, sweat gets trapped in the skin and isn’t released. This is what causes heat rash. The more a person sweats the higher their risk of heat rash.  

Sweat rash is common in:

  • Babies: Their sweat glands have not properly developed.
  • People who are new to hot climates: They’re sweating more than usual.
  • Highly active people: High levels of physical activity increase sweating.
  • People with fever: The body is sweating more to lower its temperature.
  • People wearing tight bandages: The wrapping is preventing the sweat from escaping.

Symptoms tend to appear in the folds of the skin and on areas of the body where clothing can be particularly tight. With heat rash a person may notice:

  • Tiny clear fluid-filled bumps
  • Itchy fluid-filled bumps that may appear darker than other areas of the skin
  • Firm bumps that are deeper in the skin, they may break open and are sometimes painful
Woman in bed itching a rash on her arm, possibly caused by dust mite allergy

Dust mites love your bed
and can cause rashes


Heat rash usually resolves on its own within 24 hours. But spending time in cooler areas or finding ways to reduce sweating can help your symptoms go away quicker. If symptoms are not gone within a few days, speak to your Healthcare provider. They may suggest you take corticosteroids. People with darker skin may notice changes in skin pigmentation where their skin is lighter or darker where the heat rash was.

Psoriasis rash

Psoriasis is an autoimmune condition, where skin cells grow faster than they’re supposed to. When this happens, you may notice patches of dry and scaly skin. Some people also experience joint pain as an additional symptom. Psoriasis is also a chronic skin condition, which means it can last a long time. While researchers are still understanding how changes in the immune system cause psoriasis, they think it happens when immune system cells attack healthy skin cells.

Symptoms of psoriasis can include:

  • A patchy scaly rash that in paler skin appears red, but in darker skinmay appear purple
  • Itchy skin
  • Burning sensations
  • Dry and cracked skin

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Woman in bed itching a rash on her arm, possibly caused by dust mite allergy


The options a Healthcare provider suggests depend on the severity of psoriasis.

For mild to moderate psoriasis treatment may include:

  • Topical corticosteroids:These reduce inflammation but can stop working with long-term use.
  • Vitamin-D analogues:These slow down skin cell turnover to help reduce scaling and can include creams and ointments.
  • Phototherapy:Uses artificial light to reduce symptoms.

For severe psoriasis, systemic treatments are normally needed. These work throughout your body from the inside rather than treating the skin directly.  This means they usually come in tablet form but can also be injections. 

Chickenpox rash

Chickenpox is caused by the varicella-zoster virus and is contagious, it typically affects children between the ages of 4–10. The rash tends to be very itchy and is made up of fluid-filled blisters which eventually scab over.

The blister clusters tend to cover large areas of the body and appear darker than the surrounding skin. You may first notice a chickenpox rash developing on the chest, back, face, upper arms and legs.  

Other symptoms can typically include:

  • Low-grade fever
  • Mouth sores
  • General sense of feeling unwell
  • Headache
  • Sore throat


Chickenpox usually resolves on its own but some people may need antiviral medicine. Treatment tends to focus on symptom relief, for example using lotions to soothe itchy skin. Keeping nails short or wearing gloves is also a good idea. Scratching the rash and breaking the skin can leave scarring and cause an infection.

Man lying on his back on the grass, gazing up at the sky, with his hands behind his head

Allergy symptoms from
grass and its pollen

Shingles rash

Shingles is a reactivation of varicella-zoster virus that causes chicken pox and typically occurs in adults. After a person has caught chicken pox, the varicella-zoster virus lays dormant in sensory nerve cells. The immune system keeps the virus in check, but if a person is feeling run down or has a weakened immune system the virus can reactivate and cause shingles symptoms. Like chicken pox, shingles is also contagious, and can spread to other people through inhaling droplets from sneezing and coughing, and also blister contact. A person can only develop shingles if they’ve had chicken pox first.


Because shingles can be more severe than chicken pox, a Healthcare provider may prescribe antiviral treatments within 24–48 hours of the rash developing. Similar to chicken pox, people may also want to manage symptoms, such as itching with calamine lotion. If a person has shingles, it’s important they stay hydrated and drink plenty of water.

Impetigo rash

Impetigo is a highly contagious bacterial infection, which tends to be more common in babies and young children. Impetigo can develop on its own, but insect bites and cuts can also introduce the bacteria. If you have atopic dermatitis (eczema), you could have a higher risk of developing impetigo as your skin is more vulnerable.

On paler skin impetigo causes skin redness but it may be more difficult to spot on darker skin. The sores often break open and leak fluid, eventually forming a honey-colored crust. Because the rash tends to be itchy, it’s important not to scratch as you could break the skin and introduce another infection. 


Because impetigo is caused by bacteria, usually staphylococci, antibiotics typically clear up the infection. If the rash is large a Healthcare provider may prescribe oral antibiotics in addition to topical treatments. For smaller areas, they may suggest you apply an antibiotic cream, lotion or ointment directly on the rash.

Ringworm rash

Ringworm is a contagious fungal infection. Unlike the name suggests, it’s not caused by a worm. The rash is usually itchy and has a circular shape with a clear patch in the middle. It also tends to be darker than the surrounding skin and can also be slightly raised and scaly. People are more likely to develop ringworm on the arms, legs and trunk.


Over-the-counter antifungal medication should clear up ringworm. If that’s not effective, you may need to speak with your Healthcare provider about prescription options. Treatments come in many forms. Some are tablets and others are topical. Topical treatments include creams, lotions, powders, gels and sprays.

Common skin rashes: signs and symptoms

Fingers pressing on someone’s shoulder which looks red and itchy – it’s contact dermatitis

Contact dermatitis

Contact dermatitis could happen when your body reacts to an allergen touching your skin. But it may take a few days to appear.

Raised bumps and reddened skin typical of hives, which can be an allergy symptom

Hives (urticaria)

Hives can be a symptom of allergies, for instance to food, medicine, insect venom or latex. Also to contact with grass.

Child’s back and arm covered with a rash caused by an allergic reaction to antibiotics

Drug allergy rash

Rash caused by an allergic reaction to antibiotics. It can vary in position and severity.

Scattered dark red marks on pale skin – this is milaria or heat rash, also known as prickly heat

Heat rash

Heat rash is also known as miliaria or prickly heat, it happens when sweat gets trapped in the skin and isn’t released.

Red scaly rash on someone’s elbow, typical of psoriasis on paler skin

Psoriasis rash (on paler skin)

A symptom of psoriasis is a patchy, red, scaly rash. The skin may also appear dry and cracked and can feel itchy.

Someone with darker skin showing the purple scaly rash on the sole of their foot from psoriasis

Psoriasis rash (on darker skin)

This patchy, purple, scaly rash is a symptom of psoriasis. The skin may also crack and feel dry and itchy

Child with chickenpox showing a scattered red rash on their chest and arm

Chickenpox rash

Itchy, fluid-filled blisters which eventually scab over. You may first notice a chickenpox rash developing on the chest, back, face, upper arms and legs.

The lower half of someone’s face with a honey-colored crusty blister from impetigo on their upper lip

Impetigo rash

On paler skin impetigo can appear red, but it may be more difficult to spot on darker skin. The sores eventually form a honey-colored crust.

Someone with ringworm, their arm and armpit showing the round patches typical of ringworm, red but clear in the middle

Ringworm rash

Ringworm rash can appear as round patches that are clear in the middle. The skin can also feel slightly raised and scaly.

If your skin rash appears suddenly and you have other symptoms such as shortness of breath, seek medical assistance immediately, as you could have anaphylaxis. Anaphylaxis is a severe and life-threatening allergic reaction that needs urgent medical treatment.  

You should also speak with a Healthcare provider if your skin condition is affecting your mental health. Psoriasis and frequent skin allergy flares, can, in some instances contribute to anxiety. So it’s important you seek help if your symptoms are having a negative impact on your well-being.

If your skin rash is crusting over and weeping this can be a symptom of impetigo, which is a bacterial infection. A Healthcare provider would typically treat this with antibiotics. 


Allergies can be a cause of skin rash in addition to other conditions such as infection and autoimmune conditions. Examples of allergens range from food to medicine. When a person has a life-threatening allergic reaction, it’s called anaphylaxis. Anaphylaxis is a medical emergency that requires urgent treatment, usually with epinephrine.

Other skin rashes could be a sign of an underlying issue with your immune system, such as psoriasis. Generally, skin rashes associated with autoimmune conditions can be quite complex to treat, consequently they usually take a long time to heal.

Of course, some skin rashes can clear up on their own, such as those typically seen in chicken pox and other, usually mild, viral infections. In some instances you could ask your Healthcare provider about lotions to soothe the skin until the rash clears. Other types of skin rash may need prescription treatments, especially if they’re caused by a bacterial or fungal infection.

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Last medically reviewed on 20/09/2022