A rash is a change in the skin that affects its color, appearance, texture, or smooth surface. Rashes can be caused by many factors including, but not limited to, drug reactions; allergies; bacterial, fungal or viral infections; chemotherapy; or graft versus host disease (allogeneic stem cell transplant patients only).

A skin biopsy may be needed to diagnose and appropriately treat your skin rash. Punch biopsies are typically done by taking a small sample of the skin, then closing the skin with 1 to 2 stitches. The skin sample is then examined under a microscope and a diagnosis is made.

Most skin rashes improve but require time to heal.

Signs and symptoms of a skin rash

  • Redness
  • Itching
  • Bumps
  • Hives
  • Bruising
  • Thickening of the skin
  • Dark areas in armpits, groin, or skin folds
  • Blisters
  • Skin color changes


  • Gently cleanse the affected area using lukewarm water and mild soap. Do not rub your skin. Pat the skin dry with soft towel.
  • Do not scratch or rub the affected area.
  • Do not apply any ointment, cream, lotion, or powder to the area unless it has been prescribed.
  • Do not apply cosmetics, shaving lotion, perfumes, or deodorants on the affected area.
  • Use only an electric razor if you need to shave within the affected area.
  • Do not wear tight-fitting clothing or clothes made from harsh fabrics such as wool or corduroy. These fabrics can irritate the skin. Instead, choose clothes made from natural fibers such as cotton.
  • Do not apply medical tape or bandages to the affected area unless you are told to do so by your health care provider.
  • Do not expose the affected area to extreme heat or cold. Avoid using an electric heating pad, hot water bottle, or ice packs.
  • Do not expose the affected area to direct sunlight. Sun exposure might worsen your skin reaction and lead to severe sunburn. Wear wide-brimmed hat or protective clothing to lessen sun exposure. Choose sunblock with a SPF of 30 or higher. Continue to protect yourself from the sun even after your course of treatment has been completed.
  • After transplant you have an increased risk of getting skin cancer. Therefore it is important to use a sunscreen with a SPF of 30 or greater at all times, even when there is limited direct sun exposure and especially in the winter months.

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