Cantharidin

This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.

Brand Names: US

Ycanth

Brand Names: Canada

Cantharone

What is this drug used for?

  • It is used to treat a skin problem called molluscum contagiosum.
  • It may be given to you for other reasons. Talk with the doctor.

What do I need to tell my doctor BEFORE I take this drug?

  • If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
  • If skin around the treated area is swollen or irritated.
  • If you have any blood flow problems, talk with your doctor.
  • If you have high blood sugar (diabetes).
  • If your skin has birthmarks, moles, bleeding warts, or warts with hair growth. Do not use this drug on these areas.
  • If a large area needs to be treated.

This is not a list of all drugs or health problems that interact with this drug.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take this drug?

  • Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
  • Talk with your doctor before you drink alcohol.
  • Talk with your doctor if you have a type of wart called a mosaic wart.
  • You may take OTC pain drugs as your doctor has told you.
  • Do not touch the treated area or let anyone else touch it. Do not let children or pets lick or bite the treated area. Do this for 24 hours after treatment or until you wash this drug off.
  • Do not put other drugs or products (like lotion, cream, or sunscreen) on the treated area for 24 hours after treatment or until this drug is washed off.
  • This drug may catch on fire, even after it dries. Avoid fire, flame, or smoking near the treated area until after this drug has been washed off.
  • This drug is for use on the skin only. It must not be taken by mouth. Severe side effects like stomach, kidney, and blood clotting problems; seizures; paralysis; or even death can happen if this drug is taken by mouth.
  • Do not get this drug in the eyes. Eye injury and holes in the eye can happen. If this drug gets in the eyes, flush the eyes with water for 15 minutes and get medical help right away.
  • Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Severe pain or blistering.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Skin irritation.
  • Blistering.
  • Short-term pain after use.
  • Change in color of skin where drug is used.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to your national health agency.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

How is this drug best taken?

Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Your doctor or other healthcare provider will put on the skin.
  • Do not use coverings (bandages, dressings) unless told to do so by the doctor.
  • This drug may turn the treated area a violet color. This will go away.
  • Leave this drug on the treated area for 24 hours, unless your doctor tells you otherwise. Wash it off with soap and water. Do not use a washcloth or other cloth with a rough surface. Do not rub the area firmly.
  • Talk to your doctor about what to do if you have severe pain, severe blistering, or any other severe reaction.

What do I do if I miss a dose?

  • Call the doctor for an office visit.

How do I store and/or throw out this drug?

  • This drug will be given in a hospital or doctor’s office. You will not store it at home.

General drug facts

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else’s drugs.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
  • Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.

Last Reviewed Date

2023-08-07

Copyright

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Last Updated

Monday, December 12, 2022