What is skin cryotherapy?
Dermatologic cryotherapy, also called cryosurgery, uses extreme cold to destroy a targeted skin lesion. In most clinics the freezing agent is liquid nitrogen, which boils at about −196°C.
This guide is about local skin cryotherapy for lesions such as warts, actinic keratoses and selected benign growths. It is not about whole-body cryotherapy chambers, ice baths or sports recovery.
How does liquid nitrogen destroy a skin lesion?
Liquid nitrogen rapidly freezes water inside and around cells. Ice formation, direct cellular injury and damage to small blood vessels lead to tissue death. The treated tissue then blisters, crusts or peels away while new skin heals underneath.
The depth of injury depends on how cold the tissue becomes, how long it is frozen, how large the frozen margin is and whether the clinician uses one or several freeze-thaw cycles. A longer or deeper freeze may improve clearance for some lesions, but it also increases the chance of pigment change, nerve injury or scarring.
What skin problems can cryotherapy treat?
Liquid nitrogen is commonly used for:
- common viral warts;
- some plantar warts;
- actinic keratoses caused by chronic sun damage;
- seborrheic keratoses;
- molluscum contagiosum;
- selected solar lentigines and other clearly diagnosed benign lesions.
Cryosurgery can also be used for selected low-risk skin cancers in specialist settings, but that is a different decision from routine cosmetic freezing. Cancer treatment requires careful diagnosis, margins and follow-up.
When is cryotherapy not a good choice?
Cryotherapy destroys tissue, so it is a poor choice when the diagnosis is uncertain and histopathology is needed. An atypical pigmented lesion should not simply be frozen because it “looks like a harmless spot.”
It may also be unsuitable for lesions with poorly defined borders, high-risk skin cancers, areas where deeper freezing could injure an important nerve, or situations where pigment loss would be particularly noticeable.
People with significant cold-sensitivity disorders such as cryoglobulinemia, cryofibrinogenemia or severe Raynaud disease need individual medical assessment. Previous poor healing, circulation problems and medications that affect bleeding or healing should also be discussed.
What happens during a cryotherapy session?
The clinician first confirms the diagnosis and decides how deeply the lesion needs to be treated. Liquid nitrogen may be applied with a spray device, a cotton-tipped applicator or a cryoprobe.
The skin turns white as it freezes, then thaws over the next minute or two. Depending on the lesion, a second freeze-thaw cycle may be performed. Small lesions can take only seconds to treat.
Local anaesthetic is often unnecessary, but sensitive areas, larger lesions or longer freezes can be painful.
How painful is cryotherapy?
Most people describe a sharp cold, stinging or burning sensation during freezing, followed by aching or tenderness as the skin thaws. The intensity depends on the body site, freeze duration and lesion depth.
Pain is usually short-lived, but plantar warts, fingertip lesions and deeper freezes can remain sore for longer. A blister may add pressure and tenderness during the first days.
How effective is cryotherapy for warts?
The answer depends strongly on the type of wart.
In a randomized primary-care trial, complete cure at 13 weeks was 49% for common warts treated with cryotherapy, compared with 15% with salicylic acid and 8% with a wait-and-see approach. The same study found no meaningful advantage for cryotherapy in plantar warts.
A separate multicentre trial focused specifically on plantar warts found clearance at 12 weeks in 13.6% of the cryotherapy group and 14.3% of the salicylic-acid group. In other words, freezing is not automatically the “stronger” option for a verruca on the sole.
Warts also have a natural tendency to resolve, especially in children, so treatment decisions should consider pain, duration, number of lesions and previous failed treatments.
How effective is cryotherapy for actinic keratoses?
Cryotherapy is an established lesion-directed treatment for individual actinic keratoses, but outcomes vary with technique and lesion thickness.
In a prospective study of 421 actinic keratoses, the overall complete-response rate was 67.2%. Clearance was 39% with freezes under 5 seconds, 69% with freezes over 5 seconds and 83% when freezing lasted more than 20 seconds. Longer freezing improved clearance but also means more tissue injury.
Another randomized study reported a 75% complete response at three months with cryotherapy versus 69% with photodynamic therapy. Photodynamic therapy produced better cosmetic ratings and higher patient satisfaction despite the slightly lower clearance rate.
This illustrates an important point: the most aggressive treatment is not always the best treatment when the face or scalp is being treated and cosmetic outcome matters.
How effective is cryotherapy for seborrheic keratoses and other benign growths?
Cryotherapy is widely used for thin or moderately thick seborrheic keratoses and some other benign lesions. It can be fast and effective, but the published evidence is less standardized than for warts or actinic keratoses.
Thicker lesions may need a stronger freeze, repeat treatment, curettage or another removal method. On the face, or in darker skin tones, the possibility of a pale mark after freezing may be more important than the convenience of a quick treatment.
Will I need more than one session?
Possibly. Many actinic keratoses and small benign lesions clear after one treatment, while warts often require repeated sessions. Plantar warts can be particularly resistant.
Repeating treatment should depend on the diagnosis and response. A lesion that repeatedly returns or does not behave as expected should be reassessed rather than automatically frozen again.
What will my skin look like after treatment?
Redness and swelling begin soon after thawing. A clear or blood-filled blister can appear within hours. Over the following days the area may weep, crust or form a scab.
Healing commonly takes around one to three weeks for superficial treatments, but deeper freezes and lower-leg sites can take longer. The new skin may initially look pink, lighter or darker than the surrounding skin.
What are the common side effects?
Expected short-term effects include:
- stinging, burning or aching;
- redness and swelling;
- blistering;
- crusting or temporary oozing;
- temporary tenderness.
Pigment change is one of the most important longer-term effects. Both darker and lighter marks can occur. Hypopigmentation can be especially noticeable in medium to deep skin tones because melanocytes are sensitive to freezing.
How common is pigment loss after cryotherapy?
There is no single percentage that applies to every lesion or protocol. Risk depends on skin tone, body site and freeze intensity.
In one study of patients with multiple actinic keratoses on the face or scalp who received repeated cryotherapy, hypopigmentation was reported in 54.8% of cryotherapy patients. That figure should not be applied to a brief freeze of one small wart or seborrheic keratosis; it reflects a repeated actinic-keratosis protocol. It does, however, show that pigment change is not merely a theoretical risk.
Older experimental work also found that colour changes can persist for at least six months after freezing. Patients who are particularly concerned about pigment alteration should discuss alternatives before treatment.
What rare complications can occur?
Less common complications include infection, delayed healing, permanent scarring, skin atrophy, permanent hair loss in a treated hair-bearing area and sensory nerve injury. Very aggressive freezing can cause full-thickness skin necrosis.
Reliable percentages for these rare events are not available across routine dermatologic cryotherapy because risk varies greatly by site and protocol. Reviews consistently describe scarring and nerve injury as uncommon, but they are more likely after deeper or prolonged freezing.
How does cryotherapy compare with other treatments?
The best alternative depends on the diagnosis.
- Common warts: cryotherapy can outperform salicylic acid in some common warts, but plantar warts often respond similarly to salicylic acid and freezing.
- Actinic keratoses: cryotherapy is useful for individual visible lesions. Field treatments such as topical medication or photodynamic therapy can treat a wider sun-damaged area, including lesions that are not yet obvious.
- Seborrheic keratoses: curettage, electrosurgery or selected laser methods may offer better control for some thick lesions or sites where pigment change is a concern.
- Uncertain pigmented lesions: biopsy or surgical removal is usually more appropriate because tissue can be examined under a microscope.
How should I prepare for cryotherapy?
Most small skin treatments need little preparation. Tell the clinician if the lesion has recently changed, bled or ulcerated, or if it has previously been treated and returned. Mention cold-related disorders, poor circulation, problems with wound healing and all prescription medicines.
Do not stop blood thinners or other prescribed medication on your own. For most small cryotherapy procedures, medication changes are not necessary unless your clinician specifically advises otherwise.
How should I care for the area afterwards?
Keep the area clean and let it heal naturally. A simple dressing can protect a blister or weeping surface from friction. If the blister remains intact, do not deliberately tear it open unless your clinician tells you to.
Once the surface has healed, protect the area from strong sun to reduce the chance of persistent colour change. Avoid picking crusts; this can delay healing and increase scarring.
When should I contact the clinic?
Seek advice if pain is becoming stronger rather than settling, redness is spreading, pus develops, you develop fever, the area becomes black beyond the expected treatment zone, or the wound is not healing as expected.
Also return for review if the lesion recurs quickly, changes in appearance or repeatedly needs freezing. A “stubborn” lesion sometimes needs a new diagnosis, not simply a stronger freeze.
Is cryotherapy a good treatment overall?
For the right lesion, cryotherapy is fast, inexpensive, well established and often effective. Its main limitations are equally clear: it destroys tissue without providing histology, results vary by diagnosis, and pigment changes can be more troublesome than many short descriptions suggest.
A good cryotherapy consultation should answer two questions before the liquid nitrogen is used: are we certain enough about what this lesion is, and is freezing the best balance between clearance, healing and cosmetic outcome for this particular skin site and skin tone?
