Dr Phil Kieran: What is the best way to treat my son’s verruca?

Most warts in children or teenagers will resolve within six months to two years, even if no action is taken to speed up the healing process.

My 10-year-old picked up a verruca from a hotel swimming pool while we were on holidays abroad. I know I could use an over-the-counter preparation to remove it, but I’ve heard it’s better to let it heal in its own time. 

I’m concerned that if I take this natural route, my son might pass the virus to another child at the local swimming pool.

Warts of all types are a common occurrence, with a US study showing that, at any given moment, about a third of all children and teens have warts.

A verruca is a wart on the foot. These can differ slightly from warts elsewhere in that they tend to be flat or even grow inwards, due to the pressure on the foot preventing it from growing outwards.

The virus that causes warts is generally spread from skin to skin. Warts should be covered up when going swimming, as the virus spreads more easily from softened wet skin than from dry skin. As for trying to pinpoint exactly when someone was exposed to a wart virus, this can be difficult to establish as it has an incubation period from two to six months.

Common warts aren’t dangerous or inherently problematic, but they can cause distress if they are visible or be painful if they appear on the sole, similar to having a stone in your shoe all the time, as the hard skin is pressed into the foot. 

Most warts in children or teenagers will resolve within six months to two years, even if no action is taken to speed up the healing process.

That aside, almost everyone is keen to get rid of warts as soon as possible, and I would certainly do the same for my own children.

Several treatment options are available for warts and verrucae, but it’s worth noting they often take considerable time to become effective. To get the benefit, you may need to stick with treatment for anywhere from six weeks to six months.

The first line over-the-counter treatment I usually recommend is acid-based. These treatments typically contain salicylic acid, which helps break down the surface layers of skin and encourages the immune system to clear the wart virus. This treatment should be applied regularly and continued until the wart is gone. While using this treatment, the skin will harden around the wart, and it should be removed before continuing treatment. We usually recommend using an emery board or pumice stone to do this after soaking the skin to soften it. Other than the time it takes to do this, there isn’t really a downside to using this treatment so long as the instructions are followed carefully. While generally effective, it can also be slow.

If this doesn’t work, you could consider seeing your doctor to discuss cryotherapy, a treatment where the wart is frozen to trigger inflammation and encourage the immune system to clear it. The therapy has the drawback of being somewhat painful and frequently needing repeated treatments.

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