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Topical benzocaine/menthol is primarily used to relieve pain and itching of the skin from bug bites, bug stings, and irritated skin. It works by temporarily blocking nerve signals for pain and calming the itching feeling on your skin. The most common side effects are a temporary stinging, burning, or redness where it is applied.

Uses

What is topical benzocaine/menthol used for?

Topical benzocaine/menthol is commonly used to relieve pain and itching of the skin from bug bites, bug stings, and irritated skin.

Topical benzocaine/menthol may also be used for other conditions as determined by your health care provider.

How does topical benzocaine/menthol work (mechanism of action)?

Benzocaine/menthol works by blocking nerve signals for pain and calming the itching feeling on your skin.

How is topical benzocaine/menthol supplied (dosage forms)?

Brands and other names

  • Fire Out

Dosage forms and strengths

  • 20%/1% topical solution

Benzocaine/menthol is also available in a form that is used in the mouth or throat. See Benzocaine/Menthol mucous membranes for more information. 

How should I store topical benzocaine/menthol?

Storage requirements for topical benzocaine/menthol have not been provided with the product packaging. Most medicines should be kept in a cool, dry location that is out of reach of children and pets and not in direct sunlight.

Check the product label for specific storage information. Ask your pharmacist if you have any questions about how to store your topical benzocaine/menthol product.

Side Effects

What are the most common side effects of topical benzocaine/menthol?

The most common side effects of topical benzocaine/menthol are temporary stinging, burning or redness where it is applied. Tell your health care provider if these side effects bother you.

There may be other side effects of topical benzocaine/menthol that are not listed here. Contact your health care provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of topical benzocaine/menthol?

While less common, the most serious side effects of topical benzocaine/menthol are described below, along with what to do if they happen.

Methemoglobinemia. Topical benzocaine/menthol can cause a serious blood disorder called methemoglobinemia. Hemoglobin is a protein that normally carries oxygen in your blood. Methemoglobinemia is when you have too much of a form of hemoglobin called methemoglobin. If you have methemoglobinemia, it is harder for your body to get oxygen to your tissues. Get help right away if you have any of the following symptoms of methemoglobinemia.

  • Changes in the color of your skin, including pale, gray, or blue colored skin
  • Headache
  • Fast heartbeat
  • Shortness of breath
  • Feeling lightheaded
  • Tiredness or weakness

Severe Allergic Reactions. Topical benzocaine/menthol may cause allergic reactions, which can be serious. Stop using topical benzocaine/menthol and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Warnings & Precautions

Who should not use topical benzocaine/menthol?

Allergies to Ingredients. People who are allergic to any of the following should not use topical benzocaine/menthol.

  • Fire Out
  • Benzocaine
  • Menthol
  • Any of the ingredients in the specific product you are using

Your pharmacist can tell you all of the ingredients in specific topical benzocaine/menthol products.

What should I know about topical benzocaine/menthol before using it?

Keep topical benzocaine/menthol out of the reach of children.

Do not use topical benzocaine/menthol on large areas of your body. Follow the instructions on the product you have and make sure you understand how to use it properly. Do not use it more often than the instructions say. This helps reduce your risk for serious side effects. Ask your health care provider if you have any questions about how to use the product. 

Topical benzocaine/menthol should only be used on the outside of your skin. Do not use it in your mouth. Do not allow it to come in contact with your eyes. If the medicine gets in your eye, wash your eye with water or saline right away and protect the eye until the numbing effect has worn off. 

What should I tell my health care provider before using topical benzocaine/menthol?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if topical benzocaine/menthol is right for you.

In particular, make sure that you discuss any of the following.

Pregnancy. It is not known if or how topical benzocaine/menthol could affect pregnancy or harm an unborn baby. Tell your health care provider if you are or plan to become pregnant.

Breastfeeding. It is not known if topical benzocaine/menthol passes into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed.

Interactions

Does topical benzocaine/menthol interact with foods or drinks?

There are no known interactions between topical benzocaine/menthol and foods or drinks.

It is unknown if drinking alcohol will affect topical benzocaine/menthol. 

Does topical benzocaine/menthol interact with other medicines (drug interactions)?

There are no known interactions between topical benzocaine/menthol and other medicines. Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much topical benzocaine/menthol?

If you or someone else has used too much topical benzocaine/menthol, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of topical benzocaine/menthol?

Benzocaine/menthol is meant to be used only when needed. Use it as your health care provider recommends. Do not use double or extra doses.