What are the treatment options for warts?

Treatment Options for Warts

For cutaneous (non-genital) warts, start with salicylic acid 15-40% applied daily after paring the wart, and if this fails after 3 months, switch to cryotherapy with liquid nitrogen every 2-4 weeks for 3-4 months; for genital warts, use patient-applied podofilox 0.5% solution or provider-administered cryotherapy or TCA 80-90%. 1, 2, 3, 4

First-Line Treatment for Cutaneous Warts

Salicylic Acid (Strength of Recommendation: A)

• Apply salicylic acid 15-40% topical paints or ointments daily after debriding the wart to remove the thick keratin layer that blocks treatment penetration. 1, 2
• The mechanism works through promoting exfoliation of epidermal cells and stimulating host immunity against the virus. 1
• Continue treatment for 3-4 months before declaring treatment failure, as premature switching reduces overall success rates. 2
• Critical pitfall: Avoid damaging surrounding normal skin during paring, as this spreads HPV infection to adjacent areas through autoinoculation. 2, 5
• Meta-analysis shows warts treated with salicylic acid are 16 times more likely to clear than placebo-treated warts. 1

Site-Specific Considerations for Salicylic Acid

• Plantar warts: Use 15-40% preparations; cure rates are lower due to thicker cornified layer preventing adequate penetration. 1
• Plane warts (face/hands): Use lower concentrations (2-10% cream or 12-17% paint) without occlusion to minimize scarring risk. 1
• Warts in children: Use 15-40% preparations; painful treatments should be avoided in young children when possible. 1

Second-Line Treatment: Cryotherapy

Application Protocol

• Freeze the wart for 15-30 seconds with liquid nitrogen and repeat every 2-4 weeks (or fortnightly per British guidelines) for a minimum of 3-4 months before declaring treatment failure. 1, 2, 5
• Local anesthesia may facilitate therapy when the area of warts is large. 2
• Common pitfall: Improper technique leads to overtreatment or undertreatment; substantial training is required for proper use. 2
• Cryotherapy is relatively inexpensive, does not require anesthesia, and does not result in scarring if performed properly, though patients commonly experience moderate pain during and after the procedure. 2

Combination Therapy

• If monotherapy fails, combine salicylic acid with cryotherapy, which is more effective than salicylic acid alone. 5, 6
• One study of 65 warts showed 89.2% eradication rate using combined cryotherapy with daily 70% salicylic acid application. 6

First-Line Treatment for Genital Warts

Patient-Applied Options

• Podofilox 0.5% solution is the most effective patient-administered therapy for genital warts. 4, 7

• Apply twice daily (every 12 hours) for 3 consecutive days, then withhold for 4 consecutive days; repeat this cycle up to 4 times. 4

• Limit treatment to less than 10 cm² of wart tissue and no more than 0.5 mL solution per day. 4

• Contraindication: Avoid podofilox, imiquimod, and sinecatechins in pregnancy. 7

• Imiquimod cream 5% applied 3 times per week (e.g., Monday, Wednesday, Friday) for up to 16 weeks or until total clearance. 3

• Apply prior to sleeping hours, leave on for 6-10 hours, then wash off with mild soap and water. 3

Provider-Administered Options

• Cryotherapy with liquid nitrogen (do NOT use cryoprobe in vagina due to perforation/fistula risk). 1
• TCA or BCA 80-90% applied to warts only, allowed to dry until white frosting develops; repeat weekly if necessary. 1
• If excess acid applied, neutralize with talc, sodium bicarbonate, or liquid soap preparations. 1

Site-Specific Genital Wart Treatment

• Cervical warts: Biopsy to exclude high-grade SIL before treatment; manage with specialist consultation. 1
• Urethral meatus: Cryotherapy or podophyllin 10-25% (safety in pregnancy not established). 1
• Anal warts: Cryotherapy, TCA/BCA 80-90%, or surgical removal; intra-anal warts require specialist consultation. 1

Third-Line Treatment for Recalcitrant Warts

Surgical Removal

• For large clusters or treatment-resistant warts, surgical removal via tangential excision, curettage, or electrosurgery offers 93% efficacy with 29% recurrence rate and eliminates warts in a single visit. 2, 8
• The procedure creates a wound extending only into the upper dermis since most warts are exophytic. 1, 8
• Hemostasis achieved with electrosurgical unit or chemical styptic (aluminum chloride); suturing neither required nor indicated in most cases. 1
• Particularly beneficial for patients with large number or area of warts. 1, 2, 8

CO2 Laser Therapy

• Reserve for extensive, recalcitrant cases that have failed first-line treatments; clearance rates 67-75%. 2, 8
• Significant side effects include bleeding, pain, reduced function lasting weeks, and risk of scarring. 2, 8
• Does not offer superior efficacy to other destructive methods when considering cost and accessibility. 8

Contact Immunotherapy (Strength of Recommendation: C)

• Diphenylcyclopropenone (DPC) or squaric acid dibutylester (SADBE) applied from twice weekly to every 3 weeks for 3-6 months. 5
• Consider as third-line option for multiple refractory warts on hands/forearms. 5

Intralesional Bleomycin (Strength of Recommendation: C)

• Use 0.1-1 U/mL solution injected or pricked into wart after local anesthesia; one to three treatments needed. 5

Critical Treatment Principles

When to Change Treatment

• Change modality if no substantial improvement after 3 provider-administered treatments or if warts haven't cleared after 6 treatments. 5
• Treatment duration should be adequate (3-4 months minimum) before declaring treatment failure. 2, 8

Watchful Waiting

• Watchful waiting is reasonable for new warts, as approximately 30% resolve spontaneously within 6 months. 2, 8
• In children, warts are often relatively short-lived and likely to clear within 1-2 years. 1

Important Caveats

• Plantar warts consistently show poorest outcomes compared to other body sites due to thick cornified layer preventing adequate treatment penetration. 2, 8
• Recurrence is common with all wart treatments (likely due to reactivation of subclinical HPV infection rather than reinfection). 2, 8
• More aggressive treatment regimens increase efficacy but also increase pain and risk of scarring. 2, 8
• Scarring in the form of persistent hypopigmentation, hyperpigmentation, or depressed/hypertrophic scars can occur with ablative modalities if insufficient healing time between treatments. 5

Critical Pitfall to Avoid

• Never use treatments designed for genital warts (podofilox, imiquimod) on non-genital cutaneous warts, as these are specifically indicated for genital lesions only. 2

Immunosuppressed Patients

• Treatment may not result in cure but can reduce wart size and functional/cosmetic problems. 1
• Use standard treatments with paring, salicylic acid, and destructive methods while avoiding damage to surrounding skin. 1
• Consider cidofovir (topical or systemic), contact immunotherapy, imiquimod, laser, or systemic retinoids. 1