Healthy skin provides a barrier between the inside of the body and the outside environment. A rash means that some change has affected the skin.
In many cases, rashes are caused by skin irritation, which can have many causes. A rash is often a minor problem that may go away with home treatment. But sometimes a rash doesn't go away, or the skin may get so irritated that medical care is needed.
In adults and older children, rashes are often caused by contact with a substance that irritates the skin (contact dermatitis). Contact dermatitis may cause mild redness of the skin or a rash of small red bumps. A more severe reaction may cause swelling, redness, and larger blisters. The location of the rash may give you a clue about the cause.
Contact dermatitis doesn't always occur the first time you are in contact with the irritating substance (allergen). After you've had a reaction to the substance, a rash can occur in response to even very small amounts of the substance. Contact dermatitis isn't serious, but it's often very itchy. Common causes include:
Rashes may occur with:
Rashes may also occur as a symptom of a more serious disease, such as liver disease, kidney disease, or some types of cancer.
Rashes may appear after exposure to an insect or a parasite, such as the scabies mite. You may get a rash when you travel to a rural area or go hiking or camping in the woods.
A rash may be a sign of a chronic skin problem, such as acne, eczema, psoriasis, or seborrheic dermatitis. Other causes of rashes include dry, cold weather; extremely hot weather (heat rash); and emotional stress.
Some medicines can cause a rash as a side effect. A very rare and serious type of generalized (whole-body) red rash called toxic epidermal necrolysis (TEN). TEN can cause the skin to peel away, leaving large areas of tissue that weep or ooze fluid like a severe burn. TEN may occur after the use of some medicines. If this type of rash occurs, you need to see a doctor.
The need for medical treatment often depends on what other symptoms you have. A rash that occurs with other symptoms, such as shortness of breath or fever, may mean another problem, such as a serious allergic reaction or infection.
Many things can affect how your body responds to a symptom and what kind of care you may need. These include:
You have answered all the questions. Based on your answers, you may be able to take care of this problem at home.
Sudden tiny red or purple spots or sudden bruising may be early symptoms of a serious illness or bleeding problem. There are two types.
Petechiae (say "puh-TEE-kee-eye"):
Purpura (say "PURR-pyuh-ruh" or “PURR-puh-ruh”):
If you're not sure if a fever is high, moderate, or mild, think about these issues:
With a high fever:
With a moderate fever:
With a mild fever:
Temperature varies a little depending on how you measure it. For adults and children age 12 and older, these are the ranges for high, moderate, and mild, according to how you took the temperature.
Oral (by mouth) temperature
A forehead (temporal) scanner is usually 0.5°F (0.3°C) to 1°F (0.6°C) lower than an oral temperature.
Armpit (axillary) temperature
Certain health conditions and medicines weaken the immune system's ability to fight off infection and illness. Some examples in adults are:
Abnormal bleeding means any heavy or frequent bleeding or any bleeding that is not normal for you. Examples of abnormal bleeding include:
When you have abnormal bleeding in one area of your body, it's important to think about whether you have been bleeding anywhere else. This can be a symptom of a more serious health problem.
Symptoms of serious illness may include:
Symptoms of infection may include:
Shock is a life-threatening condition that may quickly occur after a sudden illness or injury.
Adults and older children often have several symptoms of shock. These include:
Many prescription and nonprescription medicines can cause a rash. A few common examples are:
Symptoms of a severe allergic reaction (anaphylaxis) may include:
A severe reaction can be life-threatening. If you have had a bad allergic reaction to a substance before and are exposed to it again, treat any symptoms as an emergency. Even if the symptoms are mild at first, they may quickly become very severe.
Based on your answers, you may need care soon. The problem probably will not get better without medical care.
Based on your answers, the problem may not improve without medical care.
Based on your answers, you may need care right away. The problem is likely to get worse without medical care.
Based on your answers, you need emergency care.
Call 911 or other emergency services now.
Sometimes people don't want to call 911. They may think that their symptoms aren't serious or that they can just get someone else to drive them. Or they might be concerned about the cost. But based on your answers, the safest and quickest way for you to get the care you need is to call 911 for medical transport to the hospital.
Most rashes will go away without medical treatment. Home treatment can often relieve pain and itching until the rash goes away.
After a rash appears, leave it alone as much as you can.
But if you have come in contact with a substance such as poison ivy, oak, or sumac, wash the area with a lot of water right away. If you can, use liquid dish soap or a mild soap and very warm running water.
If you have a rash, you should not be in contact with children or anyone who is pregnant. Most viral illnesses that cause a rash are contagious, especially if you also have a fever.
Try these tips to help relieve itching from a rash.
Put cloths soaked in ice water on the rash a few times a day. Too much wetting and drying will dry the skin, which can increase itching.
Heat makes itching worse.
Or you can try an oatmeal bath product, such as Aveeno.
Scratching leads to more scratching. Cut nails short or wear cotton gloves at night to prevent scratching.
Don't wear wool and synthetic fabrics next to your skin.
Examples are Basis, Cetaphil, Dove, and Oil of Olay. Use as little soap as you can. Don't use deodorant soaps.
Try using ones like CheerFree or Ecover. Rinse twice to remove all traces of the soap. Don't use strong detergents.
Dry skin may make itching worse.
Carefully read and follow all label directions on the medicine bottle or box.
Take several breaks during the day to do a relaxation exercise if stress appears to cause your itching or make it worse. In particular, do it before you go to bed. Sit or lie down, and try to clear your mind. Manage your stress by relaxing every muscle in your body, starting with your toes and going up to your head. Doing this may help your symptoms.
Call a doctor if any of the following occur during self-care at home:
You can help your doctor diagnose and treat your condition by being prepared for your appointment.
Current as of:
November 15, 2021
Author: Healthwise StaffMedical Review: William H. Blahd Jr. MD, FACEP - Emergency MedicineKathleen Romito MD - Family MedicineAdam Husney MD - Family MedicineE. Gregory Thompson MD - Internal Medicine
Current as of: November 15, 2021
Author: Healthwise Staff
Medical Review:William H. Blahd Jr. MD, FACEP - Emergency Medicine & Kathleen Romito MD - Family Medicine & Adam Husney MD - Family Medicine & E. Gregory Thompson MD - Internal Medicine
To learn more about Healthwise, visit Healthwise.org.
© 1995-2022 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.