The Bottom Line

Cryotherapy is a fast, in-office dermatology treatment where liquid nitrogen (at −196°C / −321°F) is applied directly to a skin lesion to freeze and destroy abnormal cells. It is one of the most common treatments for warts, actinic keratoses (sunspots that can become cancerous), seborrheic keratoses, skin tags, and other benign growths. Most treatments take only a few seconds to a few minutes, and the treated lesion typically falls off within 1–3 weeks.

What Is Cryotherapy?

Cryotherapy — also called cryosurgery or "freezing" — is a medical procedure that uses extreme cold to destroy abnormal or unwanted skin tissue. In a dermatology office, liquid nitrogen is the most commonly used agent because of its very low temperature (−196°C), which freezes cells rapidly and reliably.

When liquid nitrogen is applied to a skin lesion, ice crystals form inside and between cells, rupturing cell membranes and destroying the tissue. The treated area then blisters, crusts, and gradually falls off over 1–3 weeks as your body removes the destroyed tissue and heals underneath.

What Conditions Does Cryotherapy Treat?

Dermatologists use cryotherapy to treat a wide range of skin conditions, including:

  • Warts (common, plantar, and flat warts caused by HPV virus) — one of the most common uses. Multiple treatments spaced 2–4 weeks apart are often needed.
  • Actinic keratoses (AKs) — rough, scaly patches caused by years of sun damage that carry a small risk of becoming squamous cell carcinoma. Cryotherapy clears approximately 75–85% of individual lesions in one treatment.
  • Seborrheic keratoses — harmless but sometimes itchy or cosmetically bothersome "age spots" or "barnacles" that appear with aging.
  • Skin tags (acrochordons) — small soft growths that hang off the skin in friction areas like the neck, armpits, or groin.
  • Molluscum contagiosum — a viral infection causing small pearly bumps, particularly in children.
  • Lentigines (liver spots / solar lentigines) — flat brown spots from sun damage.

What Happens During a Cryotherapy Treatment

Cryotherapy is performed in your dermatologist's office with no anesthesia needed for most lesions. Your doctor applies liquid nitrogen to the lesion using one of two methods: a cotton-tipped swab dipped in liquid nitrogen, or a spray gun that delivers a fine jet of liquid nitrogen directly onto the lesion.

The freeze time depends on lesion size and depth — typically 5–30 seconds for most benign lesions. You will feel an intense cold sensation followed by a brief burning or stinging feeling as the tissue freezes. This discomfort passes within 1–2 minutes of the treatment ending.

For warts on the palms or soles, where thicker skin requires more aggressive treatment, the stinging can be more noticeable and your doctor may apply local anesthetic beforehand.

What to Expect After Treatment

Over the 24 hours following cryotherapy, the treated area typically forms a blister filled with clear or slightly blood-tinged fluid. This is normal and expected — it shows the treatment is working. The blister should not be punctured intentionally, though it may break on its own.

Over 1–3 weeks, the blister dries, forms a scab or crust, and eventually falls off, leaving new pink skin underneath. Full healing takes 2–6 weeks depending on the size of the lesion and body location (face heals faster than feet).

Some temporary side effects are common: mild swelling and redness for 1–3 days, soreness at the treatment site for several days, and possible temporary darkening or lightening of skin in the treated area (more common in people with darker skin tones).

How Effective Is Cryotherapy?

For actinic keratoses, a single cryotherapy treatment clears approximately 75–85% of lesions. Wart clearance rates vary — common warts clear in 60–80% of cases after 2–4 treatments spaced 2–4 weeks apart. Plantar warts (on the soles of feet) are more resistant and may require 5–6 or more treatments. For seborrheic keratoses and skin tags, a single treatment is usually curative.

Frequently Asked Questions

How many cryotherapy treatments will I need?

It depends on the condition and your individual response. Seborrheic keratoses and skin tags typically require just one treatment. Actinic keratoses usually clear with 1–2 treatments. Warts often need 3–6 treatments spaced 2–4 weeks apart because the HPV virus can be difficult to fully eliminate. Your dermatologist will assess your response at each visit and recommend additional treatment if needed.

Will cryotherapy leave a scar?

In most cases, cryotherapy heals without a permanent scar. However, there is a small risk of permanent pigment changes — particularly pale (hypopigmented) spots in the treated area. This risk is higher in people with darker skin tones. Very aggressive freezing of large or deep lesions can occasionally cause a small scar, but for routine cryotherapy of small lesions this is uncommon.

Can I treat a wart at home with over-the-counter cryotherapy kits?

Over-the-counter cryotherapy kits (like Compound W Freeze Off) use dimethyl ether propane mixtures that reach only about −57°C — far warmer than the −196°C liquid nitrogen your dermatologist uses. They can be effective for small, superficial warts but are significantly less effective for plantar warts, large warts, or resistant cases. For anything that hasn't responded to home treatment, in-office liquid nitrogen cryotherapy is considerably more effective.

Is cryotherapy painful for children?

Children tolerate cryotherapy reasonably well for small lesions. The sensation is described as an intense cold pinch or sting for a few seconds. For larger lesions or anxious children, a topical anesthetic cream (EMLA) can be applied 30–60 minutes before the appointment to numb the area and make the procedure more comfortable. Talk to your dermatologist about this option before your child's appointment.

References

  1. Thai KE, Sinclair RD. Cryotherapy of benign skin lesions. Australas J Dermatol. 1999;40(4):175-186.
  2. Lubritz RR, Smolewski SA. Cryosurgery cure rate of actinic keratoses. J Am Acad Dermatol. 1982;7(5):631-632.
  3. Berth-Jones J, Hutchinson PE. Modern treatment of warts: cure rates at 3 and 6 months. Br J Dermatol. 1992;127(3):262-265.
  4. Zouboulis CC. Cryosurgery in dermatology. Eur J Dermatol. 1998;8(7):466-474.
  5. Pasquali P. Cryosurgery — a practical guide. Springer; 2015.
  6. Aldahan AS, Mlacker S, Shah VV, et al. Efficacy of intralesional immunotherapy for the treatment of warts: a review of the literature. Dermatol Ther. 2016;29(3):197-207.