TABLE 1.
Topical therapies for viral warts
| TREATMENT MODALITY | DESCRIPTION | MECHANISM OF ACTION | RESPONSE | ADVERSE EFFECTS |
|---|---|---|---|---|
| Salicylic acid6,7,8 | Organic acid (available as 16.7% paint and 40% in corn caps for plantar warts) | Ablates HPV infected epidermal cells and softens hyperkeratotic epidermis associated with warts. | Cure rates of up to 75% have been reported. | Potential for an irritant reaction |
| Imiquimod6,9 | Toll-like receptor 7 (TLR-7) agonist (available as 5% cream) | Significant role in induction of innate immune response | Complete clearance in 30–89% cases according to a few non-controlled trials | Erythema, flu-like symptoms, fatigue, diarrhea, fever, skin blistering, erosion, excoriation, flaking, edema, paresthesia, pruritus, burning, tenderness, stinging, crusting, rash, superficial ulcer |
| Diphencyprone6 | Sensitizing agent | Induces a local type intravenous hypersensitivity reaction. | Overall response rates of 60% have been reported. | Severe blistering or generalized eczema at the contact site |
| 5-Fluorouracil (5-FU)7 | Chemotherapeutic agent (available as 5% cream) | Interferes with the synthesis of DNA and RNA in infected cells. | 20% showed complete clearance. | Erythema, ulceration, crusting, and occasional hypopigmentation |
| Tretinoin3,7,8 | Retinoids (vitamin A analogues) (available as 0.025% and 0.05% cream) | Disrupt epidermal growth and differentiation, thereby reducing the bulk of the wart. They may also have an immunomodulatory inhibitory effect on HPV replication. | 85% clearance rate as compared to 32% in controls; used in verruca plana. | Retinoid dermatitis |
| Trichloroacetic acid (TCA)10,11 | Available in concentrations of 10–90% | Causes destruction of tissue by hydrolysis of cellular proteins leading to cell death. | 20% showed complete clearance with 40% TCA weekly after 4 weeks. Longer treatment duration or higher concentrations yield higher cure rates. Particularly used in verruca plana and plantar warts. | Itching, pain, erythema, hyperpigmentation. Rare adverse effects include infection, ulceration and scarring. |
HPV: human papilloma virus