Warts are one of the most common reasons patients visit a community pharmacy for self-care advice. Caused by the human papillomavirus (HPV), common warts (verruca vulgaris) appear most frequently on the hands, fingers and around the nails, while plantar warts (verrucas) affect the soles of the feet. They are harmless but can be persistent, cosmetically bothersome and occasionally painful — particularly on weight-bearing surfaces.

The most important thing a pharmacist can communicate is realistic expectations. Wart treatment is slow, requires patience, and no single product guarantees clearance.

The natural history of warts

Before discussing treatment, patients benefit from understanding that warts are self-limiting. According to the British Association of Dermatologists, approximately 65–80% of warts resolve spontaneously within two years without any treatment. In children, the clearance rate is higher; in immunocompromised patients, it is lower.

This means that for painless warts in non-cosmetically sensitive areas, watchful waiting is a legitimate clinical option — and in children, often the best one. Treatment should be considered when warts are painful, spreading, causing distress, or located in areas where they interfere with daily activities.

Over-the-counter treatment options

Salicylic acid preparations

Salicylic acid is the first-line pharmacy treatment for warts, recommended by NICE and the BNF. It works as a keratolytic — dissolving the thickened, virus-infected skin layer by layer.

Available formulations include:

• Salicylic acid paint/collodion (e.g. Bazuka Extra Strength, 26% w/w) — applied daily after soaking the wart in warm water and filing with an emery board
• Salicylic acid gel (e.g. Bazuka gel, 12% w/w) — forms a waterproof film over the wart
• Salicylic acid plasters (e.g. Carnation corn caps with salicylic acid) — useful for plantar warts on feet

Treatment must continue for up to 12 weeks. The evidence base, primarily from a Cochrane systematic review, suggests salicylic acid clears warts in approximately 50–70% of cases with consistent use — significantly better than placebo, but far from guaranteed.

Key counselling points:

• Soak the wart for five minutes in warm water before each application
• File away dead skin gently with a disposable emery board (do not share boards — HPV is contagious)
• Protect surrounding healthy skin with petroleum jelly
• Apply daily without missing days — inconsistent use is the main reason for treatment failure
• Expect 8–12 weeks of treatment before judging success

Over-the-counter cryotherapy kits

Dimethyl ether propane (DMEP) sprays (e.g. Bazuka Sub-Zero, Wartner, Scholl Freeze Verruca and Wart Remover) are available without prescription. These freeze the wart to approximately –57°C, compared with liquid nitrogen used in GP practices which reaches –196°C.

The evidence for OTC cryotherapy is more limited than for salicylic acid. A Cochrane review found no strong evidence that cryotherapy is superior to salicylic acid for common warts. The OTC products produce a shallower freeze than clinical liquid nitrogen, which may explain lower clearance rates.

These products are reasonable as a second-line option or for patients who find daily salicylic acid application impractical. They typically require two to three applications at two-week intervals.

Silver nitrate pencils

Silver nitrate caustic pencils (e.g. AVOCA) are available from pharmacies and work by chemically cauterising the wart surface. They are applied after moistening the tip and rubbing onto the wart for one to two minutes, then allowed to dry. Treatment is repeated every 24 hours for up to six applications.

Silver nitrate stains the skin black temporarily — patients should be warned about this. It is a useful option for small, accessible warts but is less well studied than salicylic acid.

What about duct tape?

The "duct tape occlusion" method — covering the wart with silver duct tape for six days, then soaking and filing — gained attention after a 2002 randomised controlled trial in children suggested it was as effective as cryotherapy. However, a larger subsequent trial found no significant benefit over placebo. Current NICE guidance does not recommend duct tape as a treatment for warts. Pharmacists may mention it as a low-risk option if asked, but should not recommend it as first-line.

When to refer

Pharmacists should direct patients to their GP when:

• The wart is on the face, genitals or perianal area (genital warts require specialist assessment)
• The lesion is changing in colour, shape or size and may not be a wart (differential diagnoses include seborrhoeic keratoses, squamous cell carcinoma and amelanotic melanoma)
• The patient is immunosuppressed
• Warts are extensive or rapidly spreading
• OTC treatment has been used consistently for 12 weeks without improvement
• The patient is diabetic with a plantar wart (reduced sensation and impaired healing increase risk)

The pharmacy's role

Community pharmacists see wart presentations regularly and are well placed to set realistic expectations, recommend appropriate first-line treatment, and ensure patients understand the importance of treatment adherence. With more than 13,000 pharmacies across England, the profession handles the vast majority of wart consultations without GP involvement.

For more information on pharmacy services near you, visit PharmSee's pharmacy finder. Pharmacists looking for roles in clinical consultation services can explore current vacancies.

Sources: NICE Clinical Knowledge Summary — Warts and Verrucae; Cochrane Review — Topical Treatments for Cutaneous Warts; British Association of Dermatologists; British National Formulary; PharmSee pharmacy register data (April 2026).