General How-to for Patients
1. Let it dry. I explain to patients that “It’s not a cream or a gel, it’s a glue so you need to let it fully dry.” WP dries completely within 10 to 15 minutes. This can be accelerated with a fan or hair dryer on the coolest setting. The medication should be firm to the touch; this can be tested with a cotton swab or the plastic spatula included in the treatment kit. It is important to note that the tape should not be applied until the medication is fully dried so as to not spread the application onto normal skin. Spreading the medication onto normal skin can cause irritation and possible early discontinuation.
2. Avoid skipping days. This is the most common reason for treatment failure. Warts grow quickly and need to be completely destroyed so they do not recur. So, I always tell patients not to skip days and discuss how skipped applications can lead to treatment failure. I explain that if a patient does skip an application at night, the patient should put it on in the morning. If a patient completely misses one day, then 2 days should be added to the recommended treatment time.
3. Apply to the top and sides of the wart. Most often, patients focus their application to the top of the wart. This may be appropriate for flatter warts, but any warts with height or hyperkeratosis should receive an application of WP on its sides as well. Think of WP as frosting; instead of only putting a small bit on the top as with cupcakes, the wart should be fully covered as with a sheet cake. I also tell patients if they are having a hard time getting it exactly on the wart, it is better to go a little farther onto normal skin than to put too little on.
4. Note the color, not the size. Patients are often disappointed that their wart is the same size during a follow-up appointment. However, patients are not often paying attention to the white color, a sign that the medication is working. Flat warts and genital warts will form a crust and flatten out. With these warts, patients often think that the postinflammatory hyperpigmentation indicates the wart is still present. Patients were often surprised when we performed curettage and most of the white desiccated wart was removed.
5. Discontinue use if you experience irritation. Irritation and erythema are caused by a number of reasons, including:
- The medication did not fully dry before tape was applied, and WP irritated perilesional skin;
- User error on application, causing the medication to be applied repeatedly to perilesional skin directly;
- Initial sensitivity to WP, such as in a few patients younger than 10 years who respond much faster, often in less than 5 days, but experience more burning and erythema than other patient; or
- After sustained use, WP eliminated the wart and is being applied to healthy skin.
Patients, who want to see results as soon as possible, can be overzealous and continue to apply WP even as their skin becomes severely irritated. If the wart was flat and irritation is starting to occur, then it is likely the wart has resolved and treatment should be discontinued to allow normal skin to grow in the area.
6. Treatment length varies by wart presentation. Length of treatment can vary widely depending on a number of characteristics of the wart. A filiform wart may only require 2 to 4 days of treatment, but a thick plantar wart may need several weeks of nightly application and occlusion.
Mr Leon is a dermatology physician assistant in Simi Valley, CA.
Disclosure: The author reports no relevant financial relationships.
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