Physical Modalities: Cryotherapy

Cryotherapy, or liquid nitrogen, is used to treat warts and molluscum in pediatric patients.  Due to discomfort of cryotherapy, this should be used after careful consideration because causing undue pain in treatment of a benign condition is not recommended.  Pre-treatment with EMLA cream can be helpful if treatment is necessary. Lesions are typically treated 3 times at each session.  Warts: 5-6 seconds per cycle.  Molluscum: 2-3 seconds per cycle. Cryotherapy can be applied using the end of a cotton swab, or with a specialized canister with a spray tip. Treatment can be repeated every few weeks until clearance. For treating warts it is helpful to pare the area prior to freezing to remove the hyperkeratotic debris. Expected side effects after cryotherapy include localized pain, and blistering followed by crusting. In patients with darker skin types cryotherapy may cause post-inflammatory pigment change that can be permanent.