Ask the pharmacist

Rod Tucker is a pharmacist who spent many years working in the prison service and developed an interest in dermatology. He worked with a local dermatologist and arranged to see prisoners with skin problems. In 2003 he won the primary care pharmaceutical care award for his prison-based dermatology clinics, treating several hundred people with a range of common skin conditions. Rod qualified as an independent prescriber in 2005 and worked as a member of the clinical team for an intermediate dermatology service in Hull, where he continued to treat patients with skin problems.

He is a regular contributor to the British Dermatology Nursing Journal and writes widely in the pharmacy press. He is currently a practicing pharmacist and researcher at Robert Gordon university where his research focuses on the role of pharmacists in helping patients with skin problems. He also teaches dermatology to undergraduates at Bradford University and works for the Centre for post-graduate pharmacy education centre in Manchester as a project guardian for their dermatology training programs.

Rod Tucker Pharmacist

What is a wart/verruca?

Our skin consists of two layers, an outer epidermis and an inner dermis. The cells in the epidermis are called keratinocytes and a wart is a small, rough growth on the skin that is caused by infection of the keratinocytes with the human papilloma virus (HPV).  The virus incubates for several weeks or even months and causes the infected keratinocytes to thicken and proliferate, eventually leading to the formation of a wart. There are various forms of the HPV virus which multiply best in different areas of the body, leading to a range of distinctive warts.

Warts are very common and most of us will get one at some time in our lives. Although precise figures are hard to come by, warts are rare in children under two years of age and normally first appear in early childhood and are most common during adolescence and early adulthood. 

There at least four different types of warts:

  • Common warts are the ones that normally grow on the fingers, around the nails, on the knuckles or on the back of the hand. These warts look like a solid blister and feel rough, sometimes looking like a very small cauliflower. Occasionally it is possible to see black dots on a wart and these are the ends of blood vessels which develop within the wart. That’s why picking or cutting a wart causes it to bleed. 
  • A verruca is a wart that appears on the sole of the foot. Rather than growing upwards (as with common warts) a verruca penetrates into the sole.
  • A flat wart can occur anywhere but in children, most grow on the face. These warts tend to be smoother and much smaller than common warts and sometimes flat warts grow in groups. Men can get flat warts in the beard area which often cut during shaving. Women often get flat warts on their legs. 
  • A filiform wart is long, thin, skin-coloured lesion which tends to grow on areas of the body where the skin is thin such as the face, around the eyelids, on the lips, chin or nose.

How do you get warts?

Anyone can get warts though some are more prone than others. As mentioned earlier, warts occur more frequently in children and teenagers but warts can also develop in those with a weakened immune system.

The usual method of transmission is through direct skin contact with the virus or indirectly from contaminated surfaces. The skin cells of a wart release many thousands of virus particles so it’s best to avoid scratching or picking at a wart which can spread the infection to other parts of the body.

Infection with HPV is more likely if the skin is damaged and this helps explain why children with cuts and scrapes are more susceptible to infection.

The HPV seems to survive outside of the body for extended periods of time so it is unwise to share objects such as towels with an infected person. The virus can also enter wet skin which is why a verruca is frequently picked up from walking on contaminated floors such as swimming pools or in communal changing rooms.


How long do the warts last?

It can be difficult to predict how long a particular wart might last. Some evidence suggests that in children warts can spontaneously clear after a few months and that most will have gone by two years. In adults, warts are more persistent and can last for between 5 and 10 years.


So is it worth treating a wart?

The short answer is that it depends. If the wart is not causing any discomfort, then if left alone, the wart is likely to disappear on its own over time. However, when a wart is painful and this is often true for a verruca as it can make walking painful, then the best option is to treat it. Some people may think that a wart is unsightly because it is on their hands or they simply don’t like the thought of having one and so opt to get it treated.


Treating warts in a pharmacy

The first and most important point to remember is that all wart treatments take a long time to work and the way in which many treatments work is still not completely clear. None of the commonly used therapies act directly on the virus, in other words, they are not anti-viral and most are designed to breakdown infected tissue. 

One of the most commonly used wart treatments is salicyclic acid. It is found in many over-the-counter products such as Bazuka® and Occlusal®. Salicyclic acid destroys infected skin cells which are then shed from the surface of the skin. Over time as more of the wart tissue is abolished, the wart becomes thinner making it more difficult for the virus to replicate. It is also thought that as the skin cells are killed off, they expose the virus to the immune system which slowly mounts a defense against the virus. Many of the salicyclic acid products are formulated as a gel which forms a seal over the wart.

Another over-the-counter treatment involves cryotherapy which is the application of a very cold liquid to the wart. This is used in Wartner® and the idea is to “freeze” the wart so that the tissue dies. Cryotherapy can be performed at a GP surgery and the technique involves spraying the wart with liquid nitrogen (- 1960 C) for a few seconds and then repeating the process once or twice. Wartner® uses a liquid which reaches a temperature of

– 570C so it is much less than liquid nitrogen used by GPs and so is unlikely to be as effective.

A more recent therapy involves the use of formic acid. In fact, this is the same acid present in the venom of some species of ants! Formic acid is stronger than salicyclic acid and is used in the EndWarts PEN, a device used to deliver the formic acid. The main advantage of the EndWarts pen over salicyclic acid in that the treatment is only used once a week rather than every day. A second benefit of the EndWarts PEN is that the applicator provides just the right amount of formic acid when the pressed against the wart. Unlike salicyclic acid gels, because the EndWarts PEN applies formic acid directly into the wart, there is no problem taking a bath or shower or even putting socks back on after treatment.

The EndWarts PEN appears to be very effective and in one study of 100 people with warts, there was complete clearance in 92% of those using the formic acid pen after 12 treatments compared to only 6% in those using a pen with plain water. 

The pen contains up to 30 treatments and most warts will clear after 5 to 15 treatments though this will depend on factors such as how long you’ve had the wart, your age, the site of the wart and your immune system. 

It is important to continue with treatment until the wart appears to have gone completely, otherwise the virus will continue to replicate and the wart will not clear. Missing a few days here and there won’t make much difference but because treatment takes a long time, many people become frustrated at the lack of progress and simply give up. As a wart gets smaller, you will see black dots described earlier. Once these dots have disappeared then the wart has gone and you no longer need to use the treatment.





November 2016



EndWarts PEN

An effective wart treatment with precise application. EndWarts PEN is an effective wart treatment that only takes seconds to apply and is suitable for warts that requires precise application.