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Benzocaine Side Effects

Many of us are using over-the-counter products containing benzocaine without realizing the potential for dangerous benzocaine side effects. One of the most severe potential complications is called methemoglobinemia and it can kill you. 1

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Developed methemoglobinemia after taking Benzocaine?

Benzocaine is a topical numbing agent, or anesthetic. Because of this, products containing benzocaine have been used in an attempt to treat the conditions listed below, among others: 2 3

  • Sore gums.
  • Sore throats.
  • Canker sores.
  • Teething in infants.
  • Other types of irritation in the mouth and gums.
  • Sunburn and other minor burns.
  • Insect bites.
  • Poison ivy, oak, and sumac.
  • Minor cuts and scratches.

However, the U.S. Food and Drug Administration (FDA) has recently issued a warning to the public about products containing benzocaine and the potential life-threatening complication called methemoglobinemia. 4

What Is Methemoglobinemia?

One answer to the question “What is methemoglobinemia?”, in the simplest terms, is methemoglobinemia is a blood disorder. When you have this disorder, your body produces an abnormal amount of methemoglobin. Methemoglobin is a form of hemoglobin. Hemoglobin moves oxygen throughout your body. It is the protein in red blood cells. 5

As the U.S. National Library of Medicine explains, “With methemoglobinemia, the hemoglobin can carry oxygen, but is not able to release it effectively to body tissues.” In essence, your body’s tissues cannot receive the oxygen they need to function well. 6

Another answer to the question “What is methemoglobinemia?” is that it can be a life-threatening condition in extreme cases. People have died from methemoglobinemia, and the FDA has received several reports of death due to methemoglobinemia in people after they were exposed to benzocaine-containing products. 7 8

If you develop a bluish tinge to your skin, severe shortness of breath, or other symptoms of methemoglobinemia after using a product containing benzocaine, you should seek emergency medical attention immediately. 9

Methemoglobinemia Affects Your Blood

Methemoglobinemia is a dangerous medical blood disorder that can be life-threatening, and even lethal. The FDA has warned the public about a link between over-the-counter products containing benzocaine and the possibility of developing methemoglobinemia. 10

You Need Healthy Blood to Live

You depend on your blood to deliver oxygen and nutrients to every cell in your body. 11

Your circulatory system includes your heart, blood vessels (arteries and veins), and lungs. Your arteries transport oxygen-rich blood away from your heart to distribute oxygen and other nutrients throughout your body. 12

The veins in our body transport oxygen-depleted blood back to the heart and then to our lungs. Our lungs expel carbon dioxide when we breathe out. 13

Through a healthy circulatory system, humans are able to breathe in oxygen, and deliver this oxygen and the nutrients available in the blood throughout the body. Then when one breathes out, carbon dioxide is released and the process begins all over again. 14

When something goes wrong with your blood, every cell, tissue, and organ in your body is affected. In the case of methemoglobinemia, your cells, tissues, and other organs do not receive enough oxygen to function well. 15

What Makes Up Healthy Blood?

Healthy blood is made up of solids and liquids. The liquid part is called plasma. More than 50% of your blood is plasma. Plasma is made up of water, protein, and salts. 16

The other part of your blood is made up of solids. These solids include red blood cells, white blood cells, and platelets. 17

Red blood cells are the parts of your blood that distribute oxygen throughout the body. White blood cells are part of your immune system and help your body fight infections. Platelets are what help your blood clot when you are cut or wounded in some way. 18

Red Blood Cells Carry Oxygen

Most of the cells in your blood are red blood cells. Red blood cells contain hemoglobin, which is a special type of protein. 19

The hemoglobin in red blood cells helps carry oxygen and deliver it throughout the body. Hemoglobin is also what gives red blood cells their color. 20

Methemoglobinemia Symptoms

Methemoglobinemia symptoms may appear just minutes after using a product containing benzocaine or can occur up to several hours afterwards. In addition, methemoglobinemia symptoms can occur after using the product for the very first time or after any use after the first use. 21

Methemoglobinemia symptoms may include: 22

  • Blue-colored, pale, or gray lips, skin, and nail beds.
  • Shortness of breath.
  • Fast heart rate (tachycardia).
  • Lightheadedness.
  • Headache.
  • Fatigue.

Some people are at greater risk for complications related to methemoglobinemia, and therefore should be even more aware of this benzocaine side effect. If you have the below conditions, you should be particularly cautious when using products containing benzocaine: 23 24

  • Breathing problems, including asthma, emphysema, and bronchitis.
  • Heart disease.
  • In addition, elderly people should be mindful of the fact that methemoglobinemia, a potentially life-threatening complication, has been linked to products containing benzocaine. 25 26

    Severe Benzocaine Side Effects

    When using topical products containing benzocaine, severe side effects are possible. Some of these benzocaine side effects may also be signs of methemoglobinemia. 27

    Others may not necessarily be signs of methemoglobinemia. However, if you experience any of these benzocaine side effects, you should stop using the product and contact your doctor immediately: 28

    • Headache, dizziness, or weakness.
    • Breathing problems.
    • Fast heart rate.
    • Gray or bluish-colored skin.
    • Severe burning, sensitivity, or stinging where you applied the benzocaine product.
    • Swelling, redness, or warmth where you applied the benzocaine product.
    • Blistering, oozing, or any signs of infection.

    More Benzocaine Side Effects

    Other benzocaine side effects are also possible. These benzocaine side effects may include: 29

    • Mild stinging, itching, or burning where you applied the benzocaine product.
    • Redness or tenderness of the skin where you applied the benzocaine product.
    • Dry, white flakes where you applied the benzocaine product.

    Benzocaine and Methemoglobinemia

    The relationship between benzocaine and methemoglobinemia is something to take very seriously. Just this year the FDA issued a new safety communication regarding benzocaine and methemoglobinemia. 30 31

    The agency specifically warned consumers about the potential dangers of over-the-counter benzocaine products used in an attempt to relieve sore throats, gums, and other mouth irritation. Children under 2 years of age are particularly at risk. 32

    The FDA has urged manufacturers to voluntarily stop marketing benzocaine products to children and infants for the relief of teething discomfort. In addition, the FDA said if manufacturers do not comply, the agency “will take action to remove these products from the market.” Also, the agency is requesting that companies add new warnings to all benzocaine oral health products to describe certain serious risks. 33

    These serious risks include “elevated levels of methemoglobin in the blood.” These elevated levels can lead to a dangerous medical condition called methemoglobinemia, which can potentially lead to death. 34

    Products That Contain Benzocaine

    Benzocaine products are formulated as gels, ointments, sprays, solutions, and lozenges. Brand names containing benzocaine include, among others: 35

    • Anbesol.
    • Orabase.
    • Orajel.
    • Baby Orajel.
    • HurriCaine.
    • Topex.

    Baby Orajel Danger

    In 2012, the FDA posted a safety warning cautioning consumers that babies and benzocaine were not a good mix. Among the benzocaine products noted as problematic by the FDA, Orajel and Baby Orajel were specifically mentioned as potentially dangerous for babies. This Baby Orajel danger can be life-threatening. 36

    Over-the-counter products containing benzocaine are marketed to provide temporary relief from different types of mouth and gum pain, including teething. Manufacturers have marketed some of their products containing benzocaine as being specifically for children and infants experiencing teething discomfort, such as Baby Orajel. 37

    The benzocaine Baby Orajel danger is potentially life-threatening, even lethal, according to the FDA. The benzocaine in Baby Orajel and similar products marketed for infants and children younger than 2 years of age can cause methemoglobinemia. 38

    One concern is that symptoms of methemoglobinemia in infants may be hard for parents to detect. Even if a child is showing signs of methemoglobinemia, you may not think your child’s condition is linked to an over-the-counter teething product containing benzocaine. 39

    This Baby Orajel danger, and danger from other benzocaine-containing products marketed for teething, to your child still exists, even if you don’t realize it. Just recently, the FDA has issued a new safety communication about benzocaine-containing products. 40 41

    In fact, the Baby Orajel danger and danger from other benzocaine-containing products is so severe that the FDA has urged manufacturers to voluntarily stop marketing and selling oral benzocaine products for children younger than 2 years of age. If the manufacturers refuse to comply, the FDA has indicated that it will take further action.

    The FDA has also asked the manufacturers to add a contraindication, the FDA’s strongest warning, to the labeling for all benzocaine-containing products. This contraindication is a warning to parents and caregivers not to use the products in children younger than two. The FDA says that if manufacturers do not comply with this request, the agency will take regulatory action to have these products removed from the market. 42

    Methemoglobinemia Treatment

    One of the first steps in treating methemoglobinemia is identifying this dangerous medical condition affecting a person’s blood. In addition, doctors need to know the source of the problem. 43

    Methemoglobinemia develops when the iron in the hemoglobin in a person’s blood is converted from its ferrous form to its ferric form, changing hemoglobin to methemoglobin. In healthy blood, hemoglobin carries oxygen to the tissues and organs throughout a person’s body. 44 45

    When hemoglobin changes into methemoglobin, however, sufficient oxygen cannot reach the body’s cells, tissues, and organs. This situation can be life-threatening. 46

    According to the Pennsylvania Patient Safety Reporting System, “Methemoglobin concentrations greater than 10-15% of total hemoglobin will cause cyanosis, and levels over 70% have been fatal.” Typically, “treatment involves an immediate intravenous (IV) dose of 1 to 2 mg/kg of methylene blue.” 47

    1. U.S. Food & Drug Administration. (2018, May 23). FDA takes action against the use of OTC benzocaine teething products due to serious safety risk, lack of benefit. Retrieved from https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm608325.htm
    2. Ibid.
    3. Mayo Clinic. (2017, March 1). Benzocaine (Topical Application Route). Retrieved from https://www.mayoclinic.org/drugs-supplements/benzocaine-topical-application-route/description/drg-20072913
    4. U.S. Food & Drug Administration. (2018, May 23). FDA takes action against the use of OTC benzocaine teething products due to serious safety risk, lack of benefit. Retrieved from https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm608325.htm
    5. MedlinePlus. (2018, June 4). Methemoglobinemia. Retrieved from https://medlineplus.gov/ency/article/000562.htm
    6. Ibid.
    7. U.S. Food & Drug Administration. (2018, May 23). FDA takes action against the use of OTC benzocaine teething products due to serious safety risk, lack of benefit. Retrieved from https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm608325.htm
    8. U.S. Food and Drug Administration. (2018, May 23). Drug Safety Communications. Risk of serious and potentially fatal blood disorder prompts FDA action on oral over-the-counter benzocaine products used for teething and mouth pain and prescription local anesthetics. Retrieved from https://www.fda.gov/downloads/Drugs/DrugSafety/UCM608424.pdf
    9. Ibid.
    10. Ibid.
    11. PubMed Health. (2016, August 1). How does the blood circulatory system work? Retrieved from https://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0072434/
    12. Ibid.
    13. Ibid.
    14. Ibid.
    15. U.S. Food & Drug Administration. (2018, May 23). FDA takes action against the use of OTC benzocaine teething products due to serious safety risk, lack of benefit. Retrieved from https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm608325.htm
    16. MedlinePlus. (2018, May 9). Blood. Retrieved from https://medlineplus.gov/blood.html
    17. Ibid.
    18. Ibid.
    19. American Society of Hematology. (n.d.). Blood Basics. Retrieved from http://www.hematology.org/Patients/Basics/
    20. Ibid.
    21. U.S. Food & Drug Administration. (2018, May 23). FDA takes action against the use of OTC benzocaine teething products due to serious safety risk, lack of benefit. Retrieved from https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm608325.htm
    22. Ibid.
    23. Ibid.
    24. U.S. Food & Drug Administration. (2018, May 31). Risk of serious and potentially fatal blood disorder prompts FDA action on oral over-the-counter benzocaine products used for teething and mouth pain and prescription local anesthetics. Retrieved from https://www.fda.gov/Drugs/DrugSafety/ucm608265.htm
    25. U.S. Food & Drug Administration. (2018, May 23). FDA takes action against the use of OTC benzocaine teething products due to serious safety risk, lack of benefit. Retrieved from https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm608325.htm
    26. U.S. Food & Drug Administration. (2018, May 31). Risk of serious and potentially fatal blood disorder prompts FDA action on oral over-the-counter benzocaine products used for teething and mouth pain and prescription local anesthetics. Retrieved from https://www.fda.gov/Drugs/DrugSafety/ucm608265.htm
    27. RxList. (2012, August 1). Americaine. Consumer. Images & Side Effects. What are the possible side effects of benzocaine topical? Retrieved from https://www.rxlist.com/americaine-drug/patient-images-side-effects.htm#sideeffects
    28. Ibid.
    29. Ibid.
    30. U.S. Food & Drug Administration. (2018, May 23). FDA takes action against the use of OTC benzocaine teething products due to serious safety risk, lack of benefit. Retrieved from https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm608325.htm
    31. U.S. Food & Drug Administration. (2018, May 31). Risk of serious and potentially fatal blood disorder prompts FDA action on oral over-the-counter benzocaine products used for teething and mouth pain and prescription local anesthetics. Retrieved from https://www.fda.gov/Drugs/DrugSafety/ucm608265.htm
    32. Ibid.
    33. Ibid.
    34. Ibid.
    35. Ibid.
    36. U.S. Food & Drug Administration. (2018, May 9). Benzocaine and Babies: Not a Good Mix. Retrieved from https://www.fda.gov/ForConsumers/ConsumerUpdates/ucm306062.htm
    37. Ibid.
    38. Ibid.
    39. Ibid.
    40. U.S. Food & Drug Administration. (2018, May 23). FDA takes action against the use of OTC benzocaine teething products due to serious safety risk, lack of benefit. Retrieved from https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm608325.htm
    41. U.S. Food and Drug Administration. (2018, May 23). Drug Safety Communications. Risk of serious and potentially fatal blood disorder prompts FDA action on oral over-the-counter benzocaine products used for teething and mouth pain and prescription local anesthetics. Retrieved from https://www.fda.gov/downloads/Drugs/DrugSafety/UCM608424.pdf
    42. Ibid.
    43. Pennsylvania Patient Safety Reporting System. (2005). Patient Safety Advisory. Topical Anesthetic-Induced Methemoglobinemia. Retrieved from http://patientsafety.pa.gov/ADVISORIES/documents/200503_17.pdf
    44. Ibid.
    45. American Society of Hematology. (n.d.). Blood Basics. Retrieved from http://www.hematology.org/Patients/Basics/
    46. Pennsylvania Patient Safety Reporting System. (2005). Patient Safety Advisory. Topical Anesthetic-Induced Methemoglobinemia. Retrieved from http://patientsafety.pa.gov/ADVISORIES/documents/200503_17.pdf
    47. Ibid.