How common is methemoglobinemia from benzocaine?
We have been closely monitoring this safety risk and estimate that more than 400 cases of benzocaine-associated methemoglobinemia have been reported to the FDA Adverse Event Reporting System (FAERS) or published in the medical literature since 1971.
Can topical benzocaine cause methemoglobinemia?
Benzocaine-induced methemoglobinemia is a rare complication associated with topical anesthesia and can be life-threatening. We present 2 cases of methemoglobinemia caused by topical benzocaine spray used as premedication for transesophageal echocardiography.
What local anesthetic causes methemoglobinemia?
Methemoglobinemia is a potentially severe complication of lidocaine and benzocaine, especially when used concomitantly.
Can Orajel cause methemoglobinemia?
FDA further advises that benzocaine oral drug products should only be used in adults and children 2 years and older if they contain certain warnings on the drug label because the local anesthetic benzocaine can cause the life-threatening condition, methemoglobinemia.
What are the symptoms of methemoglobinemia?
Symptoms associated with higher levels of methemoglobin are as follows:
- 3-15% – Slight discoloration (eg, pale, gray, blue) of the skin.
- 15-20% – Cyanosis, though patients may be relatively asymptomatic.
- 25-50% – Headache, dyspnea, lightheadedness (even syncope), weakness, confusion, palpitations, chest pain.
Does methemoglobinemia go away?
The condition is benign. There is no effective treatment for people with a congenital form who develop an acquired form. This means that they should not take drugs such as benzocaine and lidocaine. People who acquire methemoglobinemia from medications can completely recover with proper treatment.
What’s better benzocaine or lidocaine?
Lidocaine and benzocaine were equally efficient, and both were better than placebo in reducing pain caused by insertion of needles into the palate.
What drugs can cause methemoglobinemia?
Drugs that may cause Methemoglobinemia include nitrates derivatives (nitrates salt, nitroglycerin), nitrites derivatives (nitroprusside, amyl nitrite, nitric oxide), sulfonamides, dapsone, phenacetin, phenazopyridine, some local anesthetics such as prilocaine, topical anesthetics such as emla cream, benzocaine.
What are symptoms of methemoglobinemia?
Why is Orajel not recommended?
The FDA is taking action against the use of benzocaine products because they have the potential to cause a condition called methemoglobinemia. Methemoglobinemia is a potentially deadly condition that causes blood to carry less oxygen.
What happens to the body with methemoglobinemia?
Hemoglobin is the protein in red blood cells (RBCs) that carries and distributes oxygen to the body. Methemoglobin is a form of hemoglobin. With methemoglobinemia, the hemoglobin can carry oxygen, but is not able to release it effectively to body tissues.
What are signs of methemoglobinemia?
What does high methemoglobin mean?
Methemoglobinemia (High Methemoglobin Levels) Posted by. Methemoglobinemia (met-hemo-globin-emia) is a condition where the quantity of methemoglobin in the red blood cells is higher than normal. It is a congenital condition, meaning that it is present from birth, but can develop in life due to exposure to certain toxins.
Why does lidocaine cause methemoglobinemia?
Methemoglobinemia is a rare condition in which the iron in hemoglobin is stabilized in the ferric (Fe3+) form, making it unable to bind oxygen and leading to tissue hypoxia and possibly death. The condition may be hereditary or acquired, the latter resulting from ingestion or application of common oxidizing agents such as lidocaine.
How common is methemoglobinemia?
Methemoglobinemia is a rare blood disorder in which an atypical form of hemoglobin, called methemoglobin, is produced in abnormal amounts. While most people have less than one percent of methemoglobin in their blood, people with methemoglobinemia may have up to 20 percent of this form of hemoglobin.