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A blister is a small fluid-filled leision which may be a pinpoint to 10 millimeters in diameter. Normally a vesicle is a small blister, while a bulla is a larger blister.

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  • Infections
  • Chicken pox
  • Herpes simplex (cold sores, genital herpes)
  • Herpes zoster (shingles)
  • Impetigo
  • Contact dermatitis
  • Poison ivy
  • Inflammatory skin diseases
  • Atopic dermatitis (eczema)
  • Drug reactions
  • Burns
  • Blistering skin diseases
  • Porphyria cutanea tarda
  • Dermatitis herpetiformis

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In many cases, vesicles break easily and release their fluid onto the skin. When this fluid dries, yellow crusts may remain on the skin surface. Be sure to let your physician know if vesicles were present before you arrived at the office.

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What You Can Do

  • Use over the counter treatments like calamine lotion and hydrocortisone cream to soothe the leisions.

  • Blisters due to cold sores might respond to application of local pain killers or docosanol.

  • The fluid from the blister should be examined under the microscope (by your physician) or sent for bacterial or viral culture.

  • A skin biopsy may be needed to make a definitive diagnosis or confirm it.

  • Consult your physician if any blisters appear on your skin due to no apparent reason.

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