The purpose of the study was to see if liquid nitrogen, a commonly used treatment for warts, is more effective if it is used alone, or if it is more effective if combined with cantharidin, a topical treatment also commonly used for warts (verruca vulgaris).

Inclusion Criteria:

1. common warts on non-genital, non-facial skin
2. otherwise healthy
3. between 18-65 and able to give informed consent
4. capable of tolerating treatment

Exclusion Criteria:

1. Ill-health
2. Poor tolerance or sensitivity to treatments in study
3. <18 years old; >65 years old
4. verruca plana or condyloma acuminata
5. immunosuppression or immune dysfunction
6. significant peripheral vascular disease
7. significant sensitivity to cold
8. epidermodysplasia verruciformis
9. mosaiform warts or periungual warts