Liquid Nitrogen Treatment

Liquid nitrogen is extremely cold. It will freeze any living tissue it comes into contact with. Applying small amounts of liquid nitrogen to various skin problems is now a standard treatment. The medical term for this treatment is cryotherapy.

What is liquid nitrogen used for?

Application of liquid nitrogen is often used to treat skin lesions such as warts, molluscum and keratoses. Although the exact mechanism of action is unclear, freezing damages the treated lesion preventing its survival. Treatment rarely requires anesthesia and almost never leaves a scar.

Is liquid nitrogen treatment painful?

Applications usually last about 10-30 seconds. Try holding a cube of ice against your skin for 10-30 seconds. It is uncomfortable but usually not too painful. Liquid nitrogen applied to skin is similar but colder and most people find the discomfort quite bearable.

What can I expect from liquid nitrogen treatment?

Liquid nitrogen is applied to the top of the skin lesion. Freezing occurs throughout the area which extends slightly to the surrounding tissue. Freezing can cause a stinging, burning pain that peaks about 2 minutes after the treatment is performed.

Within minutes after freezing, surrounding skin will become red and begin to swell. In most cases a blister will actually form within 3-6 hours. Often there is a small amount of bleeding into the blister which will turn it dark purple of black. This is expected and should not be cause for concern.

The blister usually flattens in 2-3 days and sloughs off in 2-4 weeks.

How to care for the treated area

As the blister may be tender for the first few days, you may want to protect it with a band-aid. However, most often it may be left to the air.

In most cases the blister top is a good natural bandage which protects the new skin growing underneath. Attempts to remove the blister before the new skin is ready may produce scarring or infection.

Do not soak treated area (ie, wash dishes, swim, etc) during the first 24 hours.

You should gently cleanse the treated area daily with mild soap and water.

If the area is excessively uncomfortable, you may take an over-the-counter pain reliever such as

acetaminophen (Tylenol®) or ibuprofen (Advil®).

Protect the area from sun exposure while it is healing to help prevent scar formation.

If discomfort persists, report to your clinician.

Please be aware that warts, actinic keratoses, and seborrheic keratoses often require several treatments. If your skin lesion is still present after healing (usually 2 weeks), schedule a follow-up appointment; otherwise, return as instructed by your clinician.

Does liquid nitrogen treatment always work?

Usually, it does. However, sometimes thicker warts or verrucas need two or more sessions of liquid nitrogen treatment over a period of a few weeks to get to the root. It may work but is no more effective than over-the-counter treatment with salicylic acid.