Topic Overview
Healthy skin provides a barrier between the inside of the body and
the outside environment. A rash means some change has affected the skin.
Rashes are generally caused by skin irritation, which can have many
causes. A rash is generally a minor problem that may go away with home
treatment. In some cases a rash does not go away or the skin may become 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). The rash usually starts within 48
hours after contact with the irritating substance. 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 does not always
occur the first time you are in contact with the irritating substance (allergen). After you have had a reaction to the
substance, a rash can occur in response to even very small amounts of the
substance. Contact dermatitis is not serious, but it is often very itchy.
Common causes of contact dermatitis include:
- Poisonous plants, such as
poison ivy, oak, or sumac.
- Soaps,
detergents, shampoos, perfumes, cosmetics, or lotions.
- Jewelry or
fabrics.
- New tools, toys, appliances, or other
objects.
- Latex. Allergy to natural rubber latex affects people
who are exposed to rubber products on a regular basis, especially health care
workers, rubber industry workers, and people who have had multiple surgeries.
Latex allergies can cause a severe reaction.
Rashes may occur with viral infections, such as
herpes zoster; fungal infections, such as a yeast
infection (Candida albicans); bacterial infections, such
as
impetigo; and
sexually transmitted infections (STIs). 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 also appear
after exposure to an insect or a parasite, such as the
scabies mite. You may develop 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 rash include
dry, cold weather; extremely hot weather (heat rash); and emotional stress.
Emotions such as frustration or embarrassment may lead to an itchy rash.
Some medicines can cause a rash as a side effect. A very
rare and serious type of generalized red rash called toxic epidermal necrolysis
(TEN) may occur after using sulfa drugs. 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 are present. 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.
Check your symptoms to decide if and when you should see a doctor.
Check Your Symptoms
This site requires ActiveX controls and plug-ins to be enabled. If not already installed, the Free Adobe Flash Plugin is available for download.
Home Treatment
Most rashes will go away without
medical treatment. Home treatment can often relieve pain and itching until the
rash goes away.
If you have come in contact with a substance such
as
poison ivy, oak, or sumac, immediately wash the area
with large amounts of water.
After a rash has developed, leave it
alone as much as possible.
- Use soap and water sparingly.
- Leave
the rash exposed to the air whenever possible.
- Do not scratch the
rash.
If you have a rash, you should not be in contact with children
or pregnant women. Most viral illnesses that cause a rash are contagious,
especially if a fever is present.
Relief from itching
- Keep the itchy area cool and moist. 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.
- Keep cool, and stay
out of the sun. Heat makes itching worse.
- Try an oatmeal bath to
help relieve itching. Wrap 1 cup of oatmeal in
a cotton cloth or sock and boil as you would to cook it. Allow it to cool to
room temperature, and use it as a sponge and bathe in cool water without soap.
You may also buy a product at the store, such as Aveeno Colloidal Oatmeal bath.
- Avoid scratching
as much as possible. Scratching leads to more scratching. Cut nails short or
wear cotton gloves at night to prevent scratching.
- Wear cotton
clothing. Do not wear wool and synthetic fabrics next to your
skin.
- Use gentle soaps, such as Basis, Cetaphil, Dove, or Oil of
Olay, and use as little soap as possible. Do not use deodorant
soaps.
- Wash your clothes with a mild soap, such as CheerFree or
Ecover, rather than a detergent. Rinse twice to remove all traces of the soap.
Do not use strong detergents.
- Do not let
the skin become too dry, which may make itching worse.
- Take several breaks during the day to do a relaxation exercise,
particularly before going to bed if stress appears to cause your itching or
make it worse. Sit or lie down, and try to clear your mind. Managing your stress by
relaxing every muscle in your body, starting with your toes and going up to
your head, may help your symptoms.
Nonprescription medicines for itching
Carefully read
and follow all label directions on the medicine bottle or box.
- Try calamine lotion for a rash caused by
contact dermatitis, such as poison ivy or poison oak
rashes.
- For severe itching from contact dermatitis, apply
hydrocortisone cream 4 times a day until the itch is gone.
Do not use this cream on a fungal rash, because this can make the rash worse.
- Try an oral
antihistamine to help the scratch-itch cycle. Examples
include chlorpheniramine maleate, such as Chlor-Trimeton, and diphenhydramine,
such as Benadryl. Oral antihistamines are helpful when itching and discomfort
are preventing you from doing normal activities, such as work and sleep.
Antihistamines may cause drowsiness. Do not drive or operate any type of
equipment if you are taking any of these medicines. And don't give
antihistamines to your child unless you've checked with the doctor first.
Medicine you can buy without a prescription| Try a nonprescription
medicine to help treat your fever or pain: |
|---|
Talk to your child’s doctor before switching back and
forth between doses of acetaminophen and ibuprofen. When you switch between two
medicines, there is a chance your child will get too much medicine. |
Safety tips| Be sure to follow these
safety tips when you use a nonprescription medicine: |
|---|
- Carefully read and follow all directions
on the medicine bottle and box.
- Do not take more than the
recommended dose.
- Do not take a medicine if you have had an
allergic reaction to it in the past.
- If
you have been told to avoid a medicine, call your doctor before you take
it.
- If you are or could be pregnant, do not take any medicine other
than acetaminophen unless your doctor has told you to.
- Do not give aspirin to anyone younger than age 20 unless your doctor tells you to.
|
Symptoms to watch for during home treatment
Call your doctor if any of the following occur during home
treatment:
- Other symptoms, such as a fever, feeling ill, or
signs of infection, are severe or become worse.
- A rash lasts longer
than 2 weeks.
- Symptoms become
more severe or happen more often.
Prevention
If you have a known allergy, avoid contact
with the substance that causes the allergy.
Avoid all infectious
diseases that cause skin rashes, such as chickenpox, measles, and some types of
sexually transmitted infections (STIs).
Treat your skin gently:
- Do not bathe too much. Soap and water dries
your skin of the essential oils that hold in moisture.
- Do not
scratch your skin or rub it roughly with towels.
- Avoid exposure to
chemicals that may irritate the skin, such as rubbing alcohol, soaps,
detergents, or solvents.
Preparing For Your Appointment
To prepare for your appointment, see the topic Making the Most of Your Appointment.
You can help your
doctor diagnose and treat your condition by being prepared to answer the
following questions:
- What is the history of your rash, including:
- When did the rash start?
- Where
did the rash start?
- Has the rash spread?
- Has the rash
changed?
- Have you been in contact with anything that may have
caused the rash?
- Have you been around anyone recently who has a
similar rash?
- Has anything made the rash better or worse?
- Have you had this rash before? If yes:
- What were the circumstances?
- When
did you last have it?
- How was it treated?
- How long did
it last?
- What other symptoms have you had? Symptoms may
include itching, burning, stinging, tingling, numbness, pain, or tenderness to
the touch.
- Have you used a new food, medicine, or product, such as
cosmetics, cleaning agents, detergents, soaps, chemicals, fabrics, lotions, or
nonprescription medicines?
- Have you been exposed to poisonous
plants. such as poison ivy, oak, or sumac?
- Have you had any other
health problems during the past 3 months?
- Have you recently
traveled to a rural area or to another country?
- Have you been under
an unusual amount of stress at home, work, or both?
- Does anyone in
your family have a skin disorder or an allergy? If so, to
what?
- Are your shots and vaccines up-to-date?
- Do you have any symptoms of a sexually transmitted infection (STI)?
- What home treatment measures have you tried? Did they help?
- What nonprescription medicines have you tried? Did they
help?
- Do you have any
health risks?
Credits
| By | Healthwise Staff |
|---|
| Primary Medical Reviewer | William H. Blahd, Jr., MD, FACEP - Emergency Medicine |
|---|
| Specialist Medical Reviewer | H. Michael O'Connor, MD - Emergency Medicine |
|---|
| Last Revised | February 21, 2012 |
|---|
