Many cases are temporary, brought on by exposure to irritating influences like the sun. However, serious health conditions can also cause blotchy skin.
This article outlines some of the many potential causes of blotchy skin. They include skin conditions like eczema and rosacea, infections like scarlet fever and shingles, temperature exposure, stress, pregnancy, and more.
Temperature
Temperature changes can lead to changes in blood circulation in the body. When this occurs, skin color may be altered in response to either more or less blood flow.
Exposure to Cold
When you first walk out into cold weather, the blood vessels in your skin narrow. This happens to minimize heat loss from the body. It can lead to changes in the skin’s appearance, including paleness and blue mottling. The discoloration resolves on its own once your body warms up.
Some people experience blotchy skin in the cold weather due to hives. Also known as urticaria, hives are welts on the skin that can occur from an allergic reaction or, in this case, exposure to cold temperature. Hives appear as blotchy, red skin and can lead to itching and pain.
Heat Rash
Heat rash first appears as a pink rash consisting of tiny bumps. It tends to occur along the neck, chest, and upper back. Heat rash is more common in children and can occur after spending time outdoors in the heat, humidity, or sun, or after engaging in a strenuous activity.
Heat rash can cause pain, itching, and a “pins and needles” feeling. Caused by blocked-off sweat glands, heat rash can become infected and trigger a fever. If this happens, it’s time to call your healthcare provider.
Stress
Many people correctly draw a parallel between a stressful period in their lives and the condition of their skin. Stress can show up on the skin in the form of acne, eczema, and hives. Stress increases the production of cortisol, a hormone that causes inflammation. The skin could respond by breaking out in acne or eczema.
Blotchy skin caused by stress can often clear up in a few days with good skin care and an over-the-counter skin medication.
Skin Conditions
More than 85 million Americans contend with some type of skin disorder. Many of these cause skin blotchiness.
Eczema
Eczema is an umbrella term for seven different conditions that can cause inflammation and itchiness. People with dark skin may notice patches of purple or gray, while those with lighter skin may experience red blotchiness.
A dermatologist is best equipped to diagnose eczema and which type someone may have. It can be tricky since they all include common symptoms like red, scaly skin, itching, and redness.
More than 30 million Americans, including many children, have some type of eczema.
Folliculitis
Folliculitis occurs when a hair follicle becomes inflamed or infected. It starts out as small, red bumps resembling acne. It can be itchy and uncomfortable.
Folliculitis can break out on the face, arms, legs, and back after engaging in everyday activities like wearing tight clothing, shaving, or sitting in a very hot tub. (So many people get folliculitis from hot tubs that there is a condition called “hot tub folliculitis.”)
There are several other types of folliculitis, too. Some go away on their own; others require treatment by a dermatologist.
Hives
About 20% of adults experience hives at some point in their lives. The hives appear as red welts, which are large, raised bumps on the skin. They are usually very itchy and can be blanched, which means that the center turns white when you press on it.
In addition to cold exposure, you can get hives when your body reacts to an allergen found in food, plants, medications, or infections. Some people even experience them as a result of exercise.
Most cases of urticaria are temporary, but they can become chronic.
If you ever experience hives along with difficulty breathing or a feeling that your throat is closing up, seek emergency medical help. Rarely, life-threatening reactions such as anaphylaxis (an allergic reaction) can occur.
Psoriasis
Psoriasis is a chronic skin disease that speeds up the growth of skin cells. It is an autoimmune disorder, meaning that the immune system attacks the body’s own skin cells.
While normal skin cells grow and then fall off every month, the skin cells of people with psoriasis die in three or four days. But instead of falling off, they pile up on the skin and cause itching, burning, and stinging.
Depending on the severity of the condition, psoriasis can be treated with creams or ointments, medications, or ultraviolet light therapy.
Rosacea
Rosacea is a common skin condition that affects about 14 million Americans. It usually starts as a tendency to blush easily. Other symptoms include redness, acne-like breakouts, irritated skin, visible blood vessels, sensitivity to the sun, and inflammation.
The exact cause of rosacea is unknown, but it seems to be related to the immune system. Individuals with fair skin and light-colored eyes and hair are more at risk for rosacea, as are people between the ages of 30 and 50.
A family history of rosacea and a history of acne can also put people at greater risk for developing rosacea.
Sunburn
The inflammation and redness from sunburn can lead to blotchy skin. This change in color is due to sun damage. Excessive sun exposure without ultraviolet (UV) protection damages the skin cells and leads to accelerated skin aging.
Anyone’s skin can be damaged by the sun. But people with sensitive skin are at higher risk. Once your skin is already irritated, sun exposure can worsen redness, inflammation, and pain.
Protect your skin by applying sunscreen every morning, covering up in the sun, and staying in the shade outdoors.
Tinea Versicolor
Yeast on the skin causes tinea versicolor, which is a common fungal skin infection. It results in white or light brown patches on the skin, often found on the chest or back.
Oily skin can set off tinea versicolor. It tends to be most common among adolescents and young adults.
Tinea versicolor can be stubborn, often requiring multiple applications of an antifungal or dandruff shampoo to the skin. An oral antifungal medicine or topical cream may also help.
Infections
Your skin’s No. 1 job is to protect your body from disease and infection. But some infections can seemingly outmatch the skin, at least in the short term, and cause blotchiness.
Scarlet Fever
Scarlet fever, also known as scarlatina, is caused by group of bacteria (called Streptococcus) that can affect the appearance of the skin.
In addition to fever and chills, scarlet fever can cause a red, bumpy rash about one to two days after the infection starts.
The rash usually begins as flat blotches on the skin that eventually become raised. The rash usually appears on the neck and in the underarms and groin area and eventually spreads over the body.
Shingles
Shingles is caused by the herpes zoster virus that causes chickenpox and leads to a painful rash and blotchy skin.
Symptoms of shingles include:
BlistersBurningPainTingling or an “electrical” sensation
Shingles can also cause fever, headache, muscle pain, and vomiting.
Until the virus clears up on its own, you can manage the pain and symptoms with pain relievers. Shingles can recur once it has resolved, so the CDC recommends that people above age 50 talk with their healthcare provider about getting the shingles vaccine.
Pregnancy
It’s common for pregnancy to change skin tone. Changing hormones may trigger a common condition known as melasma. Sometimes called “the mask of pregnancy,” melasma causes brown patches to appear on the face, including the bridge of the nose, forehead, and chin, as well as the neck.
It can intensify after sun exposure. Melasma usually fades on its own after childbirth.
Alcohol Flush Syndrome
If you’ve ever felt your cheeks and neck flush after a few sips of a cocktail, you may have experienced alcohol flush syndrome.
Alcohol intolerance can cause skin redness, flushing, itching, and swelling. Other symptoms can include nausea and vomiting, rapid pulse, low blood pressure, headache, and diarrhea.
This signals an intolerance to alcohol, which is an inherited metabolic condition. More specifically, it means someone lacks certain enzymes that the body uses to metabolize alcohol.
Avoiding alcohol can prevent symptoms and resolve blotchiness.
Post-Inflammatory Hyperpigmentation
After a skin rash has healed, post-inflammatory hyperpigmentation (PIH) can take its place. Acne can also result in PIH, especially in people with darker skin tones.
PIH can be difficult to treat, even with such things as a prescription-strength medication, chemical peel, and laser treatment.
Since sunlight can cause hyperpigmentation to get worse, limiting time in the sun and applying sunscreen are often a part of a treatment plan.
Treatment
Knowing the cause of your blotchy skin is key to finding the proper treatment. For instance, if your uneven skin tone is caused by a sunburn, a cool bath or soothing ointment may be helpful. For people whose skin responds to changes in temperature (like cold), keeping your body warm (or cool) can help clear up blotchiness.
Contact your healthcare provider right away if you develop a rash suddenly (with or without pain or itchiness), or if an existing rash spreads rapidly across your body. This could be a sign of an allergic reaction or an infection.
Summary
Blotchy skin is a change in skin color due to a reaction or condition. Some of the causes, like cold weather exposure, can be avoided. Others, like psoriasis and rosacea, can’t.
Whatever is causing your skin to break out in blotches, the good news is that the condition is often short-lived.
See a dermatologist if blotchiness recurs without an obvious cause, worsens, or doesn’t go away.