Post Operative Instructions – Cryosurgery (Liquid Nitrogen Freezing)

Liquid nitrogen is a cold, liquefied gas with a temperature of 196 degrees below custome writing zero Celsius (minus 321 degrees Fahrenheit).  It is used to freeze and destroy superficial skin growths such as warts and seborrheic keratoses.  It can also be used to treat premalignant skin lesions known as actinic keratoses.

Liquid nitrogen causes stinging and mild pain while the growth is being frozen and then thaws.  The discomfort usually lasts less than fifteen minutes.  On the fingers, a throbbing pain will occasionally last a few hours.

After freezing, your skin will become swollen and red, and it may blister during the first 24 hours.  A scab will form and will typically fall off by itself in one to three weeks.  The skin will usually be red first and then return to its normal color.  The area may remain lighter than the surrounding skin, but that is usually a temporary change.


  1. The treated area may develop a blister during the first 24 hours.
  2. Clean the area daily with soap and water.  If the area is oozing, use peroxide or alcohol until the oozing ends.  If a blister occurs, the blister may be pierced with a sterile lancet.
  3. The initial discomfort will improve during the following day.
  4. If the blister roof is accidentally removed, apply Polysporin ointment or Aquaphor to the blister base twice daily and cover with a breathable bandage.  AVOID NEOSPORIN AS IT CAN CAUSE A RASH IN SOME PEOPLE.  Rotate the direction of the bandaid to minimize irritation.  The area can be left open at night.
  5. Contact the office if there is any evidence of infection or increasing pain.

REMEMBER:  Cryosurgery means that part of the skin has been traumatized.  Although we attempt to minimize damage, a residual mark may occur.