Over-the-counter wart freezing products such as Freeze Away usually require two or three treatments, applied every ten days, to eliminate a wart. Over-the-counter freezing products are only effective for 40 to 50 percent of warts.
A doctor can freeze a wart using liquid nitrogen, which is much colder than over-the-counter freezing sprays. Liquid nitrogen treatment is called "cryotherapy," and it is reported to be quite painful. Most warts require one to four treatments, with at least a week between each treatment, before drying up and falling off. Cryotherapy is effective for only 50 percent of warts. Doctors usually only recommend cryotherapy if salicylic acid treatment hasn't worked. Salicylic acid has to be used daily for weeks to get rid of a wart.