Written for Stock My Medicine and clinically reviewed by Hajra Dhanchora, MPharm (GPhC 2216990).
A verruca is a wart on the sole of the foot, and the reason it needs its own name is that your body weight pushes it inwards, so instead of a bump you get a flat, hard patch that hurts to walk on. Most go away on their own eventually, but "eventually" can mean two years, and they spread in the meantime. Here's how to be sure it's a verruca, how to treat it, and how to know it's on its way out.
What does a verruca look like?
A small, rough, slightly raised or flat patch of hardened skin on the sole, heel or toes, often with a rim of thicker skin around it and tiny black dots in the middle: those are clotted blood vessels, and they're the giveaway. Pinch the skin either side and a verruca hurts; press straight down and a corn hurts. Look closely and the natural lines of the skin stop at a verruca's edge and go around it, whereas they run straight through a corn or callus. A wart on the hands or fingers is the same virus with the same rough surface, just raised because nothing is pressing on it. A plantar wart is the same thing as a verruca.
What causes verrucas, and are they contagious?
The human papillomavirus, entering through tiny breaks in wet or softened skin, which is why swimming pool floors, communal showers and shared towels are the classic sources. Yes, they're contagious, mostly through contaminated surfaces rather than skin contact, and it can take weeks or months after exposure for one to appear. Children pick them up more because their immune systems haven't met the virus before. Cover a verruca with a plaster or a verruca sock for swimming, don't share towels or shoes, and don't pick at it, which spreads it to neighbouring skin and fingers.
How to get rid of a verruca
Salicylic acid is the first-line treatment with the best evidence. It peels away the infected skin layer by layer while the film it dries to stops the virus shedding. Bazuka Gel (12%) is the standard; Bazuka Extra Strength (26%) is the pharmacy step-up for thick, established verrucas. The routine is nightly: soak, dry, apply a drop to the verruca only, and once a week rub the dead skin away with the emery board. Expect up to 12 weeks. Freezing (Bazuka Sub-Zero at home, or liquid nitrogen at a podiatrist) destroys the tissue in one or two sessions but hurts, and a GP will freeze only if a verruca is painful or persistent. Duct tape has been studied and the results are unconvincing. Home "verruca root removal" videos are a route to infection; there is no root, just infected skin. Everything we stock is in the foot care range.
Verruca treatment for kids
Salicylic acid gels are licensed for children with an adult applying them, and most children's verrucas clear faster than adults' because their immune response catches up. Because the treatments take weeks and the verruca is harmless, many GPs suggest simply covering a child's painless verruca and waiting. Treat it if it hurts, spreads, or the child is self-conscious about it. Never use salicylic acid on anyone with diabetes or poor circulation, and keep it off the face and healthy skin.
The stages of a verruca dying
People search for this because progress is slow and hard to read. The sequence as treatment works: the surface turns white and soft after each application; the black dots darken, then break up and disappear; the verruca shrinks and flattens; the skin lines start to run back through the area; and finally the patch looks like normal skin, sometimes slightly pink, with no dots. If the dots are gone and the skin lines are back, stop. If it hasn't changed at all in 12 weeks, change approach.
When to see a GP or podiatrist
If you have diabetes or poor circulation in the feet (never self-treat); if it's on the face or genitals (genital warts are a different treatment); if it bleeds, changes colour or shape, or grows quickly; if it's very painful; or if it hasn't cleared after three months of proper treatment. A podiatrist can pare it down, freeze it, or use stronger acids. Our pharmacist can check a photo description if you're unsure what you're looking at.
Verruca, corn or callus: the quick comparison
A verruca has black dots, interrupts the skin lines, hurts when squeezed from the sides, and can appear anywhere on the sole, often in clusters. A corn is a cone of hard skin with a clear centre and no dots, sits over a pressure point such as a toe joint, hurts when pressed straight down, and the skin lines run through it. A callus is a broad area of thickened skin with no defined centre, usually painless, on the ball of the foot or heel. Corns and calluses are caused by friction and shoes, not a virus, and salicylic acid corn plasters treat them; verrucas are an infection and need the antiviral approach described above.
How long does a verruca last if you leave it?
About two thirds clear on their own within two years as the immune system recognises the virus, faster in children and slower in adults. That's why leaving a painless verruca alone is a legitimate option. The case for treating is pain, spread to other sites or people, and the simple fact that two years is a long time. Immune-suppressed people (chemotherapy, transplant medicines, some arthritis drugs) clear verrucas slowly and should see a GP rather than self-treat.
Warts on hands and fingers
The same virus on the hands produces raised, rough, cauliflower-textured warts, most often on the fingers, knuckles and around the nails. Treatment is the same salicylic acid routine, but the skin is thinner than on the sole so use the standard strength, not extra strength, and stop if the surrounding skin gets sore. Warts around the nail are stubborn and can distort nail growth; a GP or podiatrist can freeze them. Never treat warts on the face, and see a GP for those.
Freezing at home versus at the podiatrist
Home freeze kits use a dimethyl ether spray that reaches about minus 50°C, enough for small, recent verrucas, and often needs two or three applications a fortnight apart. Podiatrists and GPs use liquid nitrogen at minus 196°C, which is more effective, more painful, and blisters for a few days. Freezing suits people who can't commit to twelve weeks of nightly gel; salicylic acid suits children and anyone who wants the gentler option. Neither is guaranteed first time, and combining the two (acid between freezing sessions) is a common podiatry approach.
Preventing verrucas
Flip-flops or pool shoes in communal showers and changing rooms, drying feet properly including between the toes, not sharing towels or socks, and covering any verruca you have with a waterproof plaster before swimming. Keep feet in good condition: cracked, softened or sweaty skin is what the virus gets into.
Frequently asked questions
Can I get rid of a verruca overnight?
No. Freezing is the fastest, and even that takes a week or two for the tissue to come away. Anything promising overnight results is selling something.
Can I swim with a verruca?
Yes, with it covered by a waterproof plaster or verruca sock. That's how you stop passing it on.
Why does my verruca keep coming back?
Treatment stopped when it looked better rather than when it was gone, or the virus re-entered through the same wet-floor route. Continue for two weeks past the last visible sign and wear flip-flops in shared showers.