Warts and verrucas Ngā unahiaua me ngā tona

Warts are caused by strains of the human papillomavirus (HPV). The strains that cause warts on your hands, legs or feet are different to those that cause genital warts and cervical cancer.

Warts form when the HPV virus infects the top layer of your skin and causes your skin cells to grow very fast. Warts can range in size from a few millimetres to over 1 cm across.

There are different types of warts, which look different and appear on different parts of the body.

• Common warts are usually found on fingers or toes, around the nails and on the knees. They sometimes look like a tiny cauliflower. 
• Verrucas or plantar warts are found on the soles of your feet. They grow inward into the foot and can be quite painful when you stand or walk. They can have small black pinpoint dots. 
• Plane warts have a flat surface and are usually skin coloured or a reddish brown. They are often found in clusters. 

Warts are common in school‑aged children, but they can happen at any age.

Warts are usually harmless. Most go away on their own within months, but sometimes it can take years from them to disappear. You may want to treat them if:

• they spread
• they cause pain
• you do not like the way they look.

Treatment will often clear warts and verrucas more quickly, but it can be time-consuming and uncomfortable or painful.

If you have diabetes, or a condition that affects blood flow or feeling in your feet or legs, talk to your healthcare provider before using any products to treat warts or verrucas yourself.

You may like to get your verruca treated by a podiatrist  (foot specialist) .

Find a podiatristexternal link

There are a range of treatment options. Consider using the least painful methods first, especially for children.

Duct tape

Covering a wart with duct tape is a painless way of treating warts. You can buy duct tape from a hardware store.

Follow these steps:

1. Cut a circular piece of tape in a size that just covers the wart and place it on the wart.
2. Leave it in place for 6 days (if it falls off, replace it).
3. After 6 days, take the tape off and soak the wart in warm water.
4. Gently scrape off any dead white skin with an emery board, nail file or pumice stone.
5. Leave it uncovered overnight then put a new piece on the next morning.
6. Keep doing this for 2 months, or until the wart goes away, whichever comes first.

Treating warts with duct tape takes time but can be as effective as freezing warts with liquid nitrogen.

Wart paints, gels or pastes

Wart paints, gels or pastes are treatments you put on the wart or verruca. They contain salicylic acid, podophyllin or similar ingredients. They work by removing the dead surface skin to make the wart smaller. 

Follow the instructions on the packaging about how and when to apply the treatment. Applying these treatments to normal skin that is not affected can burn your skin.

About 70% of warts improve within 12 weeks of daily treatment.

Freezing treatment 

Freezing treatment is when liquid nitrogen is sprayed or dabbed onto the wart. Liquid nitrogen is very cold, and the freezing and thawing destroys the wart. This is also called cryotherapy.

Freezing treatment is normally repeated every 1 to 3 weeks. It is very effective, with 70% of warts improving after 3 to 4 freezing sessions.

There are some down sides to freezing treatment including:

• it is quite uncomfortable when applied
• your skin may blister for a few days or weeks
• it can cause a permanent white mark or scar
• it can cause temporary numbness.

Cryotherapy (liquid nitrogen)

Other treatments

If these treatments do not clear your warts or verrucas, there are other options. These can include having the wart:

• surgically removed
• burned off.

Usually these treatments are only done by a podiatrist (foot specialist) or a dermatologist (specialist skin doctor) if other options have not worked.

Warts do not spread very easily. But it is possible to spread them by having close contact with someone else. The virus can also be passed on to someone else by touching contaminated objects or surfaces. These include:

• the area surrounding a swimming pool
• public showers
• towels, razors and other personal items.

You are at greater risk of getting warts if you:

• take medications that suppress your immune system
• have broken skin such as cuts, hangnails, closely bitten nails or scrapes on your skin
• spend time in shared, warm, damp places such as showers, locker rooms and swimming pool areas
• are a swimmer, as you can get verrucas from having moist, softened feet that have skin broken by rough pool surfaces.

You can prevent warts and verrucas by:

• wearing jandals or sandals in shared showers at pools or gyms
• not scratching warts and then biting your nails or putting your finger in your mouth
• always washing your hands after touching warts
• not sharing towels, socks or shoes
• not sharing equipment used on feet such as files or pumice.

If you have a wart, avoid scratching or picking at it. This will reduce the chances of spreading warts to other areas of your body.