Benzocaine

Benzocaine is found in many over-the-counter products, including creams, gels, liquids, ointments, pads, sprays, lozenges and swabs. It is also available in some prescription medications.

People use these products for their numbing effects. Orajel, Americaine and Cetacaine are among the many name-brand products that contain the anesthetic.

Minor side effects of benzocaine include skin rash and irritation. The U.S. Food and Drug Administration warns against using over-the-counter benzocaine products to relieve teething pain in infants because the anesthetic can cause a rare, sometimes fatal blood condition called methemoglobinemia.

Benzocaine is a chemical compound derived from para-aminobenzoic acid and ethanol. It is a white, odorless, crystalline powder. It acts on neuronal membranes and blocks nerve signals in the body. Its numbing effects are temporary.

People use the anesthetic to relieve pain or discomfort. It is not recommended for long-term use. The gels, creams and other products can treat insect bites, minor cuts and scratches, and exposure to poison ivy, oak or sumac. The medication also provides relief for canker sores, cold sores and fever blisters. It’s also used to treat vaginal and rectal irritation and is sometimes used in sexual enhancement products to desensitize male genitalia.

Benzocaine is the active ingredient in many over-the-counter analgesic products. The gels and creams relieve pain, itching and other irritations. The numbing agent is also the main ingredient in a number of sprays and lozenges that can treat mouth and throat pain.

One 2022 clinical study noted that topical anesthesia with 60% lidocaine was more effective than 20% benzocaine in reducing pain severity during dental procedures.

Health care professionals also use the sprays to numb the lining of the mouth and throat during procedures and to suppress the gag reflex. Such procedures include inserting instruments down the throat to view internal organs, and inserting breathing tubes and feeding tubes. Benzocaine products are not FDA-approved for these uses.

The FDA and the Mayo Clinic offer several precautions to take when using products that contain the topical anesthetic.

• Don’t use benzocaine products if you have ever had methemoglobinemia.
• Don’t use more than the smallest amount of this medication needed.
• Don’t apply benzocaine more than four times a day.
• Don’t get the product in your eyes.
• Avoid swallowing the gel, liquid or ointment.
• Don’t apply benzocaine products to open wounds, burns, broken or inflamed skin.
• Don’t use the product near an open flame or while smoking because benzocaine is flammable.
• Don’t use benzocaine to treat certain kinds of skin infections or serious problems, such as severe burns.
• Stop using this medicine and check with your doctor right away if you or your child have a skin rash, burning, stinging, swelling, or irritation of your skin.

The absorption of benzocaine into the bloodstream through the skin is more significant when you apply the product on broken skin, such as a wound or burn, and an overdose can be fatal. To avoid overdosing, use only the minimum amount needed. A doctor will be able to advise you on the proper dosage. If you suspect an overdose, contact poison control or an emergency room right away.

When to Talk to Your Doctor

In general, you should ask your doctor for guidance before you use the numbing medication. This is especially true if you are taking medicines that contain nitrates, including nitroglycerin. Also discuss benzocaine use with your physician if:

• You have any blood disease or genetic enzyme deficiency
• You have heart disease
• You have lung or breathing problems, including asthma, bronchitis or emphysema

Benzocaine use during pregnancy is generally thought to be safe, but it hasn’t been studied thoroughly. You should talk to your doctor before using the medication if you are pregnant or may become pregnant.

The U.S. Food and Drug Administration issued a safety bulletin on May 23, 2018, stating that benzocaine oral drug products should not be used in children 2 and under. The FDA also called for warnings on product labels about the link to methemoglobinemia.

The bulletin applied to over-the-counter benzocaine products used for teething and mouth pain as well as prescription local anesthetics, including articaine, bupivacaine, chloroprocaine, mepivacaine, prilocaine, ropivacaine and tetracaine.

The agency noted the products can cause methemoglobinemia, “which can be life-threatening and result in death.” According to a 2013 study in the Journal of the American Dental Association, most cases of methemoglobinemia have occurred following a “significant” overdose of the drug. But even small amounts can be dangerous to infants.

The FDA urged manufacturers of over-the-counter oral benzocaine products to add warnings to their label about methemoglobinemia. The agency urged label changes that also directed the products not be used for teething or for any reason in children younger than 2.

Following the FDA announcement, attorneys began preparing benzocaine lawsuits against manufacturers on behalf of infants, children and adults who developed methemoglobinemia after using over-the-counter oral health products that contain the numbing agent.

Alternatives for Teething Pain

The FDA says the risks outweigh any potential benefits of using benzocaine to treat teething pain in children under 2. The agency suggests following the recommendations of the American Academy of Pediatrics instead.

The academy says to gently rub or massage the child’s gums with your finger. You can also give the child a firm, rubber teething ring. The academy says frozen teething rings get too hard and can cause more harm than good.

The academy also recommends against using teething tablets that contain the plant poison belladonna.