In most adults, a rash can be mild and resolve on its own. But if you have other symptoms, such as fever, pain, or a rash that spreads, you may need urgent medical care.
A rash is an area of skin that may be inflamed, irritated, itchy, bumpy, or blistered.
It may also present differently depending on your skin tone.
For instance, people with lighter skin tones often see rashes that are pink, red, or purple. People with darker skin might develop rashes that are white, gray, or darker than the surrounding skin.
Most rashes are mild and may be treated with over-the-counter remedies.
However, rashes may also be a sign of a condition that requires medical treatment, such as infection, allergic reaction, or disease.
Keep reading to learn more about 12 signs that indicate you should see a doctor for your rash.
When to call 911
A rash can be a sign of a serious medical emergency called anaphylaxis.
Call 911 or get immediate medical attention if you have a rash and any of these is occurring:
- It is spreading rapidly.
- You’re having trouble breathing.
- You have a high fever.
- You feel lightheaded or dizzy.
- You’re nauseous.
It’s best not to drive yourself in any of these scenarios. If your reaction is anaphylaxis you could become unconscious in just a few minutes.
A fever is a key sign that a rash should be examined by a doctor, according to the American Academy of Dermatology Association (AAD).
Fever, along with a rash, may be a sign of an allergic reaction or several types of infection, such as:
It’s possible for a rash to also become infected. Signs of an infected rash include pain, swelling, oozing of pus, and crusting. It’s important to see a healthcare professional if you experience an infected rash.
A rash that is spreading is another sign to seek medical care.
It might be a warning that an infection or allergic reaction, such as contact dermatitis, is causing your rash.
Sometimes, a swollen rash spreading quickly may also indicate a medical emergency, such as anaphylaxis. It’s best to go to an urgent care center or the emergency room if your rash is spreading rapidly.
A painful rash may indicate a medical condition, such as shingles. This type of rash usually affects one side of your stomach, chest, and back.
Other symptoms of shingles may include a tingling, itchy, or burning sensation in the affected area.
A painful rash may also indicate cellulitis, which is a skin infection that requires immediate medical attention.
A sudden rash may be an allergic reaction to a medication, known as a drug allergy.
According to the American College of Allergy, Asthma, and Immunology, common drug allergy triggers include:
Sometimes, a rash may develop in the first few weeks after you start a new medication. If this occurs, let your doctor know as soon as possible, as waiting too long may lead to more serious reactions.
In some cases, drug allergies may also cause anaphylactic shock, which may lead to difficulty breathing, swelling in the throat, and dizziness. This a medical emergency.
Sometimes, rashes can blister.
Some causes of blistering rashes may heal on their own, such as sun exposure and poison ivy.
However, blistering rashes may indicate conditions that require medical treatment, such as shingles and an autoimmune condition called pemphigus vulgaris.
Rashes damage the skin’s surface, making it easy for infections to develop, especially if you scratch the rash.
According to the AAD, symptoms of an infected rash may include:
- pain
- warmth
- swelling
- crusting
- yellow or green discharge
- a bad smell
Difficulty breathing that accompanies a rash is a sign of anaphylaxis, which is a medical emergency.
This might happen when you eat or drink something you’re allergic to.
Learn more about the 9 most common food allergies.
A rash resembling large purple patches or dark bruises can indicate a serious condition, such as vasculitis and deep vein thrombosis.
A medical professional can determine what’s causing this rash and start treatment.
An insect bite may cause a rash with bruising, swelling, or pain.
Speak with a doctor if you notice this symptom, as bruising may be a warning that the poison from the bite could be cutting off blood flow to the area.
A circular-shaped rash could indicate Lyme disease, most commonly caused by tick bites.
Lyme disease normally causes a rash that resembles a bull’s eye and symptoms similar to the flu. The rash usually appears within 4 weeks of the tick bite, but may take up to 3 months.
It’s important to see a healthcare professional as soon as possible. Early treatment with antibiotics could help prevent lifelong complications, such as chronic fatigue and muscle weakness.
Other causes of circular rash may include:
- ringworm (tinea corporis)
- granuloma annular
- sarcoidosis
- lupus
A rash that persists for more than 1 week is worth getting looked at by a medical professional.
There might be a reason your body is having trouble healing the rash. Plus, even if your rash is mild, a medical professional may recommend over-the-counter and home remedies.
It’s a good idea to get any rash that causes you significant discomfort or concern checked out by a healthcare professional.
While it might be simple contact dermatitis, it’s still a good idea to consult a doctor.
How can you tell if a rash is serious?
Signs of a serious rash may include bleeding, oozing, and serious pain. A rash accompanied by symptoms like difficulty breathing, dizziness, and throat swelling is a sign of a medical emergency.
How long should a rash last before seeing a doctor?
Speak with a healthcare professional if a new rash doesn’t improve after 2 days.
What does a cancerous rash look like?
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What does a leukemia rash look like?
A leukemia rash may look different from person to person but may include tiny bumps (petechiae), papules on the skin, plaques, and bruising.
Rashes are a common skin condition. Most rashes are temporary and clear up on their own.
However, a rash can signify something more serious that could require medical treatment.
Rashes that occur along with trouble breathing, fever, lightheadedness, or nausea, are a medical emergency.