Liquid nitrogen is used by dermatologists for a variety of purposes.  Most commonly, it is used to treat warts, pre-cancerous growths, "age warts", skin tags and molluscum contagiosum.  Liquid nitrogen treatments are safe when done properly. 

What is Liquid Nitrogen and How Does it Work?

Nitrogen is a gas that makes up most of the air we breathe.  When it is made very cold (-196 °C) it becomes a liquid.  When this liquid is applied to warts (or other skin growths), it causes a separation in the skin.  The top layer peels off within 1-3 weeks and takes all or part of the original growth with it.  

What are the Side Effects of Liquid Nitrogen Treatments?

  • Treatments with liquid nitrogen are uncomfortable for a brief period of time.  Some people report tenderness for up to a week or longer when plantar warts are treated.   
  • Liquid nitrogen treatments frequently cause blistering or scabbing which is normal.   
  • Sometimes, liquid nitrogen leaves the skin a whitish colour after the skin growth that has been treated "falls off" and heals.  Sometimes the skin returns to normal but occasionally it remains lighter than the surrounding skin.  
  • In darker-skinned individuals, liquid nitrogen treatments can frequently cause a darkening of the skin.  This is usually temporary but can be very slow to resolve
  • Rarely, liquid nitrogen treatments can cause a scar.  This is unusual

How Should I Take Care of the Sites where I have been Treated with Liquid Nitrogen?

  • If blisters develop they can be popped with a sterile needle if desired.
  • Apply Vaseline ointment twice per day to any areas treated on the face. 
  • Protect the skin from the sun while it is healing (and always) by wearing sun-protective clothing or a broad-spectrum sunscreen with an SPF of 30 or higher