What is the treatment for warts after multiple cryotherapy (cryosurgery) treatments?

Treatment Options for Warts After Multiple Cryotherapy Treatments

When cryotherapy has failed after multiple attempts, switching to a different treatment modality is strongly recommended, as continuing with the same ineffective approach is unlikely to yield results. 1

Assessment of Treatment Failure

Before selecting an alternative treatment, consider:

• Number of previous cryotherapy sessions (treatment should be changed if no substantial improvement after 3 sessions or no complete clearance after 6 sessions) 1
• Location of warts (warts on moist surfaces typically respond better to topical treatments than those on dry surfaces) 1
• Patient tolerance and preferences

First-Line Alternative Treatments

Patient-Applied Options:

1. Salicylic Acid (SA) Preparations (15-26%)

   • Apply daily after removing thick keratin layer
   • Use occlusion when possible
   • Continue for 3-4 months
   • Strength of recommendation: A 1

2. Imiquimod 5% Cream

   • Apply once daily at bedtime, three times weekly for up to 16 weeks
   • Wash treatment area with soap and water 6-10 hours after application
   • Acts as an immune enhancer that stimulates interferon and cytokine production
   • FDA-approved for genital warts 2
   • Can be combined with salicylic acid for plantar warts to enhance penetration 3

Provider-Administered Options:

1. Trichloroacetic Acid (TCA) or Bichloroacetic Acid (BCA) 80-90%

   • Apply small amount only to warts until white "frosting" develops
   • Powder with talc or sodium bicarbonate to neutralize excess acid
   • Repeat weekly as necessary 1

2. Podophyllin Resin 10-25% in Compound Tincture of Benzoin

   • Apply small amount to each wart and allow to air dry
   • Limit application to <0.5 mL or area <10 cm²
   • Consider washing off after 1-4 hours to reduce irritation
   • Repeat weekly as necessary 1

3. Surgical Removal

   • Options include tangential scissor excision, shave excision, curettage, or electrosurgery
   • Advantage: usually eliminates warts in a single visit
   • Best for patients with large or numerous warts 1

Second-Line/Alternative Treatments

1. Bleomycin Intralesional Injection

   • 0.1-1 mg/mL solution injected into wart after local anesthesia
   • One to three treatments
   • Note: Painful during and after treatment
   • Strength of recommendation: B 1

2. Contact Immunotherapy

   • Using agents like diphencyprone (DPC) or squaric acid dibutyl ester (SADBE)
   • Applied every 1-3 weeks for 3-6 months after initial sensitization
   • Strength of recommendation: C 1

3. Laser Therapy

   • Particularly pulsed-dye laser after paring and/or SA pretreatment
   • Usually requires 2-4 treatments
   • Strength of recommendation: C 1

Treatment Algorithm Based on Wart Location

For Hand Warts:

1. First try: Salicylic acid preparations (15-26%)
2. If no response: Imiquimod 5% cream or TCA/BCA
3. If still resistant: Consider surgical removal or bleomycin injection

For Plantar Warts:

1. First try: Combination of imiquimod 5% with salicylic acid solution (15%)
   • This combination has shown better efficacy than cryotherapy alone for plantar warts 3
2. If no response: TCA/BCA or surgical options

For Genital Warts:

1. First try: Imiquimod 5% cream (apply 3 times weekly for up to 16 weeks) 2
2. If no response: TCA/BCA or surgical removal
3. For extensive cases: Consider laser therapy

Important Considerations and Caveats

• Treatment Duration: Many patients require a course of therapy rather than a single treatment. Allow sufficient time (3-6 months) for treatment to work 1

• Monitoring for Side Effects: Watch for:

  • Hypopigmentation or hyperpigmentation (common with ablative methods)
  • Scarring (uncommon but possible, especially with insufficient healing time between treatments)
  • Chronic pain syndromes (rare but potentially disabling) 1

• Wart Duration: Warts present for less than 6 months have significantly higher clearance rates (84%) compared to those present longer than 6 months (39%) 4

• Treatment Expectations: Even with optimal therapy, complete clearance rates for warts range from 39-49% for common warts and may be lower for plantar warts 5

• Spontaneous Resolution: Some warts resolve without treatment, particularly in children and young adults, so watchful waiting remains an option for non-painful, non-spreading warts 5