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Skin Problems


Prevention - Home Treatment - When to Call a Health Professional

A rash (dermatitis) is any irritation or inflammation of the skin. Rashes can be caused by illness, allergy, or heat, and sometimes by emotional stress. For rashes related to childhood illnesses, See Childhood Rashes. If the rash developed after you were bitten by a tick, See Tick Bites.

Poison ivy and other plant rashes are often red, blistered, and itchy and appear in lines where the leaves brushed against the skin.

When you first get a rash, ask yourself these questions to help determine the cause (also See Skin Problems See Childhood Rashes):

  • Did a rash that is contained to a specific area (localized) develop after you came in contact with anything new that could have irritated your skin: poison ivy, oak, or sumac; soaps, detergents, shampoos, perfumes, cosmetics, or lotions; jewelry or fabrics; new tools, appliances, latex gloves, or other objects? The location of the rash is often a clue to the cause.

  • Have you eaten anything new that you may be allergic to?

  • Are you taking any new medications, either prescription or nonprescription?

  • Have you been unusually stressed or upset recently?

  • Is there joint pain or fever with the rash?

  • Is the rash spreading?

  • Does the rash itch?

    The oil on the leaves of these plants can cause an uncomfortable, itchy, red skin rash with blisters or hives.


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  • If you are exposed to poison ivy, oak, or sumac, wash your skin with dish soap and water within 30 minutes to get the allergy- causing oil off your skin. This may help prevent or reduce the rash. Also wash your clothes, your dog, and anything else that may have come in contact with the plant.

  • Avoid products that cause the rash: detergents, cosmetics, lotions, clothing, jewelry, etc.


    Shingles (herpes zoster) is caused by the reactivation of the chickenpox virus in the body years after the initial illness. The virus usually affects one of the large nerves that spreads outward from the spine, causing pain and a rash in a band around one side of the chest, abdomen, or face. The rash will blister and scab, then clear up over the course of a few weeks.

    No one knows what makes the virus active again. Shingles can affect anyone who has had chickenpox. However, older adults and people with weakened immune systems are more likely to get shingles. People with weakened immune systems include those who have had a bone marrow or an organ transplant; have cancer, especially of the lymph system; or are infected with HIV.

    Exposure to the shingles rash can cause chickenpox in a person who has not had chickenpox before.

    If you suspect shingles, call your doctor or advice nurse to discuss medication that can limit the pain and rash. If possible, call within 1 day after the rash starts.

  • Use fragrance- and preservative-free or hypoallergenic detergents, lotions, and cosmetics if you have frequent rashes.

Home Treatment

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  • Wash affected areas with water. Soap can be irritating. Pat dry thoroughly.

  • Apply cold, wet compresses to reduce itching. Repeat frequently. Also See Relief From Itching.

  • Leave the rash exposed to the air. Baby powder can help keep it dry. Avoid lotions and ointments until the rash heals. However, calamine lotion is helpful for plant rashes. Use it 3 to 4 times a day.

  • Use hydrocortisone cream to provide temporary relief of itching. Use very sparingly on the face and the genital area.

When to Call a Health Professional

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  • If signs of infection develop:

    • Increased pain, swelling, redness, or tenderness.

    • Heat or red streaks extending from the area.

    • Discharge of pus or honey- coloured crust.

    • Fever of 37.8°C (100°F) or higher with no other cause.

  • If you suspect a medication reaction caused the rash.

  • If a rash occurs with fever and joint pain.

  • If a rash occurs with a sore throat. See Scarlet fever.

  • If a rash appears and you aren't sure what is causing it.

  • If a rash continues after 2 to 3 weeks of Home Treatment.


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