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Terms Of Use


Brand Name(s) : Acnisal, Bazuka, Compound W, Occlusal, Thwart, Verrugon, Wartex
Side Effects


Salicylic acid should be used with caution in:

  • Broken, inflamed or damaged skin, such as cuts and grazes

It should not be used in:

  • Allergy (hypersensitivity) to salicylic acid
  • Diabetes
  • Poor blood circulation
  • On moles, birthmarks, unusual-looking warts with hair growth
  • If you are unsure that you have a wart, verruca, corn or callus

Also see list of precautions and interactions


Store below 25°C and keep away from flames or sources of heat.


What is it used for?

  • Salicylic acid is used to treat and remove raised warts (usually found on the hands, elbows or knees) and warts on the feet (verrucas), to remove the thick, hard pads of skin on your feet (corns and calluses) that are caused by pressure and friction.
  • It is a type of keratolytic.
  • It is used to break down a protein which forms part of the structure of the skin called keratin. In so doing, the skin is shed from the treated area. This process will remove warts and verrucas, leaving the healthy skin underneath.
  • In general this drug is used to remove warts and verrucas, and to treat and prevent acne.

Listed below are the typical uses of salicylic acid:

  • Warts
  • Verrucas
  • Corns and calluses

On occasion your doctor may prescribe this medicine to treat a condition not on the above list. Such conditions are listed below.


How often do I take it?

  • Use salicylic acid exactly as your doctor or pharmacist has told you.
  • Use this medication regularly in order to get the most benefit from it.
  • It may take up to 2 weeks before the full benefit of this drug takes effect.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • Avoid use on broken or inflamed skin, normal skin and large areas of skin. Avoid contact with the eyes, mouth and nose. Avoid the face in preparations meant for use on warts and verrucas. Avoid applying excessive amounts of salicylic acid. This drug is not suitable for use on the face, sexual organs (genitals) or bottom (anus). Avoid flames or sources of heat as salicylic acid can be volatile and highly flammable and catch on fire. Avoid inhaling any vapour from the gel. Consult your doctor or pharmacist for more details.

When can I stop?

  • Continue to use salicylic acid until the wart, verruca, corn or callus disappears. For recommended length of treatment, follow instructions on the patient information leaflet.


  • Tingling sensation and mild tenderness in treated area
  • If the gel comes into contact with normal skin, you may experience redness, rash or itching
If any of these persist or you consider them severe then stop using it and inform your doctor or pharmacist.

Tell your doctor immediately if you develop any of the following symptoms:

  • Feeling or being sick
  • Ringing in your ears

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking salicylic acid, tell your doctor or pharmacist if you are allergic to it; or to other keratolytics; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have:

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following:

  • None known

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Alcohol is not known to affect this drug.

Pregnancy and breastfeeding - please ensure you read the detailed information below


The safety of salicylic acid has not been established during pregnancy. Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


The safety of salicylic acid has not been established in breastfeeding.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Before using this medicine, tell your prescriber of all the medicines you are taking including prescription medicines and medicines you have bought over the counter without a prescription. Tell your prescriber if you are taking vitamins or complementary remedies such as herbal products, as these can also interact with medicines.

There are no known significant interactions between salicylic acid and other medicines. If you experience any unusual symptoms while using this medicine with other medicines, tell your prescriber.

If you have a question or want to discuss anything about your medicine, speak to your local pharmacist.


Excessive use of salicylic acid may cause irritation of the skin, If this occurs, stop using it until the irritation goes away. When you re-start treatment, be careful to apply less of the drug. In extreme cases of excessive use over a long time or if you swallow the drug, you may experience ringing in your ears and feel or be sick. If this occurs, stop using the drug and contact your doctor.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of salicylic acid or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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