Freezing a wart off, or cryotherapy, can be done by a doctor or at home. If freezing involves liquid nitrogen, a healthcare professional should perform the procedure.

One way doctors can remove warts is by freezing them. This is also known as cryotherapy. During treatment, a doctor directly applies liquid nitrogen, a very cold substance, to the warts. This causes the warts to freeze off.

Read on to learn about cryotherapy, including how it compares to other treatments for warts, what the procedure is like, and the recovery process.

Learn more: What’s causing this raised bump on my skin? »

Most warts that aren’t in the genital area can be treated using cryotherapy. Research suggests that cryotherapy may be particularly effective in treating warts of the hand, even when compared to traditional topical creams. Cryotherapy may also be helpful in treating plantar warts on feet.

You may be a good candidate if over-the-counter (OTC) treatments like salicylic acid haven’t successfully treated your warts. Cryotherapy may also be a good option if you want to quickly treat your wart.

People who are sensitive to pain, such as young children and the elderly, may have difficulty with the procedure.

Cryotherapy can usually be done at your doctor’s office. During the procedure, your doctor cuts your wart with a small, sharp knife. Then they apply the freezing substance with a cotton swab or spray. Liquid nitrogen is usually used as the freezing substance, though carbon dioxide may also be used.

Cryotherapy may hurt. In some cases, your doctor may apply a local anesthetic to your wart to avoid causing pain during the treatment. The procedure doesn’t take much time. For larger warts, you may need follow-up sessions to reapply cryotherapy to those warts.

Cryotherapy involving liquid nitrogen should only be performed by a healthcare professional.

You may be able to use an OTC product, such as Compound W Freeze Off or Freeze Away Easy Wart Remover, to treat smaller warts at home. These kits use a mixture of propane mixed in dimethyl ether. Typically, a foam applicator is soaked with this mixture. You apply the applicator directly to your wart. Remember to follow all instructions carefully for optimal results and minimal pain.

You may have some pain for up to three days following the procedure. You should be fully recovered within two weeks.

There’s a chance for minimal scarring. You may also develop a blister over the site of the wart. If the blister breaks, clean the area with an antiseptic wipe. This will minimize the spread of virus from the wart.

In most cases, the blister and wart will disappear within a few days. If the blister is still giving you pain or still contains fluid after this, call your doctor for a second evaluation.

There’s limited research on the effectiveness of cryotherapy for the treatment of warts. An older study from 2002 found that duct tape occlusion therapy was more effective at treating the common wart than cryotherapy. According to the study, cryotherapy successfully treated warts in 60 percent of participants. Duct tape occlusion therapy was successful for 85 percent of participants. Duct tape occlusion therapy should only be performed by a certified professional.

More research is needed to better understand the efficacy of cryotherapy in the treatment of warts.

Cryotherapy for warts is generally safe, but it has some risks. The biggest possible complication is infection of the wound, usually by bacteria. Symptoms include:

  • increased swelling
  • throbbing pain
  • fever
  • yellow discharge
  • pus

Bacterial infections can be treated using oral antibiotics.

Some other possible complications of cryotherapy include:

  • damage to your nerves, which can lead to temporary numbness
  • slow healing
  • ulcer formation
  • long-lasting scar or altered pigmentation
  • skin lesions

Cryotherapy can be an effective treatment for nongenital warts that provides minimal scarring. It’s typically used if topical treatments aren’t effective alone in treating warts. More research is needed to understand its efficacy, but most dermatologists offer it as a potential treatment.