Freeze warts, fibromas & keratoses in seconds: The CryoPen O+ in everyday practice

✏️ Author: Dr. Daniel Pehböck | 📅 February 2026 | ⏱️ approx. 9 min read

Warts, fibromas, actinic keratoses – benign skin changes are among the most common consultation reasons in general medicine and dermatology. Cryotherapy with the CryoPen O+ offers a fast, precise, and almost painless treatment method that acts in seconds and does not damage surrounding tissue. In this article, you will learn everything about the functionality, indications, and practical application of the CryoPen O+ starter set in your practice.

What is Cryotherapy? The Principle of Targeted Freezing

Cryotherapy – from the Greek "kryo" for cold – is an established dermatological procedure in which skin changes are destroyed by targeted cold exposure. The mechanism of action is based on the controlled formation of intra- and extracellular ice crystals, which lead to local tissue necrosis. The dead tissue is then expelled by the body and replaced with healthy tissue.

The CryoPen O+ uses nitrous oxide (N₂O) as a refrigerant, reaching temperatures of up to –89 °C. Compared to liquid nitrogen (N₂, –196 °C), N₂O offers significant practical advantages: it can be safely stored in compact cartridges, requires no complex cooling chain, and allows for particularly fine, controlled application.

There are basically two procedures in cryosurgery:

The CryoPen O+ primarily works in the spray method: a fine high-pressure jet is guided contact-free over the skin change at a distance of 0.5 to 3 mm. This is not only more hygienic than contact methods but also allows for greater penetration depth and more targeted