13 Causes of Red Spots on Skin

Red spots on the skin have a variety of possible causes. For example, contact with something irritating can cause dermatitis, a fungal infection is responsible for ringworm, burst blood vessels cause spots known as purpura, and some autoimmune conditions can cause rashes.

Some spots will go away on their own, but others may need treatment.

This article reviews 13 possible causes of red spots on the skin and whether they are cause for concern, as well as when to seek immediate medical care.

Heat Rash (Milaria)

Red spots on the skin after being in the sun can be caused by a condition called "heat rash." Heat rash (miliaria) happens when sweat glands are blocked under the skin. This causes small, red, prickly bumps on the skin that can be itchy or painful.

Heat rash usually appears in skin folds or on areas of skin where sweat accumulates, such as the armpits, chest, back, arms, and groin.

People who live in hot climates, sweat a lot, or are on prolonged bed rest are more likely to get heat rash.

Heat rash can be treated by lowering the temperature of the skin using home remedies like cooling baths, cold compresses, and wearing loose-fitting clothing. It also helps to avoid slathering on thick moisturizers that trap heat against the skin.

Heat rash usually gets better on its own in a few days. However, if the skin is injured, it can lead to a secondary infection. In severe cases, oral or topical antibiotics are needed to relieve pain and clear up the infection.

Call your healthcare provider if you notice any signs of infection, including a whitish coloring over the heat rash, flaking skin, or a pus-like discharge.

Cherry Angiomas

Red spots on the skin can sometimes be a cherry angioma (or cherry hemangioma), a small skin growth that appears as a round red or purple spot made up of blood vessels. The bumps can be raised or flat. The growths might be mistaken for a tumor, but they are not cancer.

Cherry angiomas are common in adults aged 30 and older. They often show up on the torso, but they can also develop on the arms, legs, and scalp. Sometimes, the growths change in size and may bleed, but this does not mean there is a problem.

Cherry angiomas are diagnosed by having a provider look at them. Usually, they do not require treatment. However, if the look of the growths bothers you or they tend to bleed, you can have them taken off.

Your provider can explain the options for removing the growths, like lasers or liquid nitrogen. Usually, these procedures do not hurt.

Contact Dermatitis

Red spots on the skin can also be from contact dermatitis, a common skin condition. It occurs when your skin comes into contact with something that is irritating or that you are allergic to.

Contact dermatitis usually shows up as an itchy red rash with bumps. It can also cause swollen, dry, flaky skin on any part of the body.

There are two main types of contact dermatitis:

• Irritant contact dermatitis occurs when the skin's protective barrier is weakened and the skin becomes irritated by a substance.
• Allergic contact dermatitis occurs when the immune system reacts abnormally to an allergy-causing substance (allergen).

Sometimes, it's easy to figure out what caused the skin reaction—for example, you walked through some poison ivy. If you are not sure what caused the rash, your provider may want you to do a patch test to find out if you are allergic to something that caused the skin reaction.

Contact dermatitis will often clear up on its own in a few weeks as long as you avoid the substance that caused it. Treatment for contact dermatitis depends on the cause but can include over-the-counter (OTC) hydrocortisone cream or prescription oral antihistamines to help with the itching.

Ringworm (Tinea Corporis)

Red spots on the skin can be from infections like ringworm (tinea corporis). Ringworm is a common fungal skin infection that causes red, blotchy, circular rash with raised edges. Ringworm can also cause flaking and peeling skin, but it usually does not hurt.

You can get ringworm on any part of your body, but it's most often found on the arms and legs.

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Ringworm is highly contagious. It's very easy to spread it through skin-to-skin contact or by touching contaminated objects or surfaces. Pets can also transmit the fungus that causes ringworm.

A provider can diagnose ringworm based on how it looks. Most cases of ringworm can be treated with over-the-counter (OTC) or prescription antifungal cream. If it's not treated properly, ringworm can spread and may require an oral antifungal drug to clear up.

Atopic Dermatitis (Eczema)

Red spots on the skin can be from chronic skin conditions. For example, atopic dermatitis (eczema) is a common skin disorder that causes red, itchy, scaly rashes usually in skin folds such as the elbows, neck, wrists, and behind the knees or ears. Eczema can also be found on the feet, toes, and fingers.

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Atopic dermatitis is usually seen in children under the age of 5. It can usually be diagnosed by a provider through a physical exam.

The treatment for atopic dermatitis usually includes topical steroid creams, antihistamines, or oral steroids for more severe cases. Experts also recommend keeping the skin well moisturized to reduce flare-ups.

Some people with eczema notice redness and itchiness after they take a shower. This can happen if you take hot or long showers or use products that irritate your skin, which dry it out.

Drug Rash

Red spots on the skin can also be a reaction to or a sensitivity to an allergen. One example is a drug rash, which occurs when your body has an allergic reaction to a medication. It can also be caused by a drug hypersensitivity or be a side effect of a medication (photosensitive reactions). Drug rashes can appear as hives, rashes, or blisters.

Drug rashes can range from mild to severe. Some cases may even require emergency care. A drug rash can affect the whole body or just one part. It tends to be spread out (diffuse) over the skin.

A provider will review all of the medications and supplements you're currently taking to figure out if the rash you have could be caused by one of them.

If the condition does not get better after you stop taking a medication, your provider may prescribe treatments such as steroids or antihistamines to help reduce swelling and pain.

Pityriasis Rosea

Red spots on the skin of kids and teens can be from a condition called pityriasis rosea. It is a common rash that usually affects adolescents, teens, and young adults. It is not a serious condition (benign).

Pityriasis rosea usually starts with one larger red spot on the chest, torso, or back that's followed by smaller red spots that have a ring-like shape. The spots can be scaly and itchy.

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Experts don't know what causes pityriasis rosea, but it is believed to be linked to a viral or bacterial infection. It often shows up after an infection. Sometimes, a person also has a headache, sore throat, and fever.

Pityriasis rosea is usually diagnosed by its appearance. Sometimes, it will disappear on its own in six to eight weeks. Your provider may give you steroids, antihistamines, or antiviral drugs to help relieve itching and swelling from the rash.

Blood Spots (Purpura)

Red spots on the skin can also be blood spots (purpura). These red or purple-colored spots may show up on your skin or inside your mouth in small or large patches. Purpura happens when small blood vessels burst and blood pools under the skin.

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Blood spots themselves are not necessarily a problem, but they can be a sign of a more serious medical condition. For example, when they are widespread it can be a sign of a blood clotting disorder.

Your provider will do a physical exam and order blood tests (including checking your platelet count) to help diagnose the cause of the blood spots.

Steroids are sometimes prescribed for purpura. Intravenous (IV) medications might be needed if a person with purpura has a low platelet count.

Swimmer's Itch (Cercarial Dermatitis)

Red spots on the skin after swimming can be from "swimmer's itch (cercarial dermatitis)" As the name suggests, it's an itchy, bumpy, red rash that occurs after swimming in water that's contaminated with parasites known as schistosomes. The parasites can be found both in freshwater and saltwater habitats.

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The rash typically develops within a day of exposure to the contaminated water. The rash is not contagious but it does need to be treated.

Topical steroids and oral antihistamines can treat the symptoms, and antibiotics might be needed if the infection doesn't get better.

Psoriasis

Red spots on the skin can be caused by a chronic autoimmune disorder that affects the skin, like psoriasis. This condition is triggered by stress, medications, infection, injury, or environmental factors. A psoriasis rash is itchy and red with silvery plaques, most often on the elbows, and knees. The plaques form when the immune system overproduces skin cells.

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A provider can diagnose psoriasis by how it looks. Sometimes, a skin biopsy is used. The treatment for psoriasis depends on how severe the lesions are but can include topical steroid creams, immune suppressant drugs, and UV light therapy.

Cold compresses, moisturizers, and oatmeal baths can also reduce itching from psoriasis.

Lichen Planus

Red spots on the skin can also be caused by other autoimmune diseases. For example, lichen planus causes red spots on the inside of the mouth, nails, scalp, genitals, eyes, throat, and digestive tract. It typically appears as a flat, itchy, purple rash.

The cause of lichen planus isn't well understood, but some experts think there could be a genetic component to the condition. Lichen planus is more common in women and people between the ages of 30 and 60.

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Lichen planus is not contagious. Sometimes it will clear up without treatment but it can also be a problem that comes back.

A provider can diagnose lichen planus with a physical exam. They may recommend treatment with topical steroids, topical retinoids, or oral antihistamines.

Petechiae

Red spots on the skin that look like a rash but are not are often petechiae. These are small red dots that look like a rash. They occur when tiny blood vessels beneath the skin burst. Petechiae tends to be smaller and more diffuse than cherry angiomas.

Petechiae often appear suddenly on the arms, legs, stomach, and buttocks. They are not raised but can spread to different parts of the body and form larger patches. The spots usually do not itch.

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Petechiae is actually not a condition but a symptom of an infection, trauma, a bleeding disorder, or an allergy.

A provider can look at the spots to figure out what is causing them. For example, fungal, viral, or bacterial infections like strep throat and scarlet fever are known to cause petechiae.

If there's no sign of infection and the spots are not spreading, petechiae may not need to be treated. However, if a person also has a fever it can be a sign of a serious infection that needs to be treated right away.

Pimples (Acne Vulgaris)

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Red spots on the skin are commonly just pimples (acne vulgaris), or inflamed red spots on the face, chest, and upper back. The pimples form when pores become blocked by oil, dead skin cells, and bacteria.

Mild acne can often be treated at home with over-the-counter (OTC) acne products. A more severe form of acne, called cystic acne, may require treatment by a dermatologist.

Treatment for acne includes topical acne medications, oral antibiotics isotretinoin, steroid injections, chemical peels, and hormonal contraceptives.

When to See a Healthcare Provider

Red spots on your skin can have many causes and you may not be able to figure out why you have them without seeing a provider. They can look at the appearance and severity of the rash, your medical history, and any underlying conditions you have.

In general, red flag symptoms along with red spots on your skin include:

• Fever
• Fatigue
• Trouble breathing
• Severe pain or swelling
• Pus oozing from the rash

If you have red spots on your skin and "red flag symptoms," seek medical care right away.

Summary

Red spots on the skin can have many causes. Some are not serious and will get better on their own without treatment. Other underlying causes are serious and may need to be treated.

Conditions like heat rash, cherry angiomas, lichen planus, and pityriasis rosea often do not need treatment. Acne, atopic dermatitis, contact dermatitis, petechiae, psoriasis, purpura, ringworm, and swimmer's itch may need to be diagnosed and treated by a dermatologist or other medical specialist.