Please note images are for illustration purposes only and may differ from the product(s) you receive

Avoca Caustic Pencil 40%

Be the first to review this product Click here
Avoca Caustic Pencil contains silver nitrate in a reusable applicator for treatment of verrucas, warts and skin growths.
Only 2 left

With well-established antiseptic and antimicrobial properties, silver nitrate from an applicator or pencil is applied topically usually in aqueous solution and used as a haemostatic, for pain relief in certain conditions and for the removal of small quantities of unwanted tissue.  Avoca Silver Nitrate Caustic Applicators and Silver Nitrate Caustic Pencils are widely used throughout the world by physicians, surgeons, nurses, midwives, podiatrists, dentists, general practitioners and veterinary surgeons.

Uses include nongenital warts and verrucas, granulation tissue, wound healing, stoma maintenance, umbilical stumps, cautery, anterior epistaxis, vasomotor rhinitis, post-bioptic cervical nicks, skin tags and pain relief for aphthous stomatitis.

Write Your Own Review
You're reviewing:Avoca Caustic Pencil 40%
Your Rating
Active ingredient: Silver Nitrate 40% w/w

The treated surface layer of warts and verrucas should be filed away using a fine emery board, for some types of verruca it will be necessary to cut away the hard callous-like surface to get to the soft tissue underneath. Repeat this treatment for remaining wart/verruca tissue until the wart/verruca has gone.

Gently stir the tip of the pencil in a drop of water for about 20 to 30 seconds.

Silver nitrate from the tip is quickly dissolved in the water. Although the appearance of the water does not change, it is now rich in silver nitrate and any absorbent material (clothing, furniture etc.) that comes into contact with this water will turn black in time depending on exposure to light.

Touch the area to be treated with the wet tip so that silver nitrate solution is transferred to the area to be treated. Use light pressure, do not press or rub the area with the tip – silver nitrate is brittle and may break if too much pressure is applied. Take care to prevent solution wandering on to neighbouring skin by protecting the surrounding tissue with a barrier such as petroleum jelly.

For warts, the treatment should be used once a day for 3 days, for verrucas, the treatment should be used one a day for 6 days.

See label before use. Silver nitrate must not be used on genital warts or near eyes.

Caution : these pencils are EXTREMELY fragile. You should use them carefully and not press too hard on the affected area. A broken tip is the result of using too much pressure.

Standard Delivery

Standard Mainland UK delivery is £3.95* 

We aim to deliver orders within 3-5 working days to the shipping address provided by you in your order if the shipping address is in the UK.  For orders being delivered outside mainland UK, this will be longer and we cannot give a guaranteed delivery time due to the differences between carriers. Delivery timescales are estimates only. If you do not receive your order within 14 days of us confirming your order has been sent you must notify us and we will investigate the non-delivery provided. Orders from outside the UK have varied delivery charges, depending on the particular country.  Please note that in some instances you may be required to answer product related questions from our Pharmacist as part of the checkout process.  Failiure to answer these will cause delays.  Please allow extra time for Pharmacy approved products.  Please note that Bank Holidays do not count as working days.

Delivery charges for orders outside the UK will vary. *Northern Ireland delivery charges different

Express UK Delivery

Express Mainland UK delivery is £6.95*, non mainland islands may vary

Please note that Express delivery is only available on orders placed before 1pm (GMT) Monday to Friday in the UK.  After 1pm we cannot guarantee express delivery, even if it has been selected.  Please note that this is not a guaranteed next day service, but is an expedited delivery option.  Products which need to be approved by a pharmacist are not suitable for express delivery.

*Northern Ireland delivery charges different

Free Delivery on orders over £50*

This applies to orders delivered to UK addresses only.  *Exclusions may apply.


We hope you will be happy with any items you’ve ordered from us, but if you’re not entirely satisfied, you’ll find details of our returns policy on the link below.

Delivery outside of the EU

Please note that certain medicines and medical devices sold on this website cannot be purchased if you live outside of the European Union.


Please visit our Delivery & Returns page for more information.