It is the active ingredient in many overthecounter anesthetic ointments such as products for oral ulcers. Methemoglobinemia can cause lifethreatening hypoxia associated with cyanosis and dyspnea not responsive to oxygen. We report two cases of methemoglobinemia due to topical benzocaine spray used as premedication for transesophageal echocardiography. Jan 23, 2008 methemoglobinemia is a rare cause of hypoxemia, characterized by abnormal levels of oxidized hemoglobin that cannot bind to and transport oxygen. Benzocaine methemoglobinemia symptoms and lawsuits. Primary care physicians family physicians and general internists perform many of the endoscopies in this country eg, approximately 17% of upper gi endoscopies in medicare beneficiaries.
Methemoglobin results from the presence of iron in the ferric form. Benzocaine ethyl aminobenzoate, used routinely as a topical oropharyngeal anesthetic for transesophageal echocardiography tee, has been reported to rarely cause methemoglobinemia. Methemoglobinemia, betaglobin type, is caused by a mutation in the hbb gene. Benzocaine induced methemoglobinemia is a potentially lifethreatening complication. Methemoglobinemia is a common adverse effect of prilocaine see also benzocaine above. Prompt management with intravenous methylene blue should be initiated for reversal. Topical benzocaine was applied orally for the relief of. Fda warns of methemoglobinemia with benzocaine topical. Risk of serious and potentially fatal blood disorder. The cause of methemoglobinemia was 20% benzocaine spray used for local anesthesia before intubation. Benzocaine spray is a local anesthetic commonly used for topical anesthesia of mucous membranes before endoscopic procedures. In a retrospective cohort study of 50 children aged 331 months undergoing infiltration anesthesia of the scalp before craniofacial surgery, lidocaine 1% with adrenaline caused this complication in.
A healthy 14 month infant developed severe cyanosis 2030 minutes after topical application of a benzocaine containing gel administered for relief of teething discomfort. Acute methemoglobinemia induced by topical benzocaine and. We describe a patient with respiratory failure following trauma who. Jan 24, 2004 benzocaine has been reported to cause methemoglobinemia when applied to infants as an ointment or a rectal suppository 2, 3 and when used topically to the perineal area. Benzocaine is a common topical anesthetic that has the ability to induce methemoglobinemia methgb in large doses. Patients dramatically improved after 1% methylene blue at 12 mgkg iv over 5 minutes. Methemoglobinemia from topical benzocaine cleveland clinic. Increased levels of methemoglobin in the blood are secondary to congenital. Benzocaine ethyl aminobenzoate is a topical anesthetic widely used for oropharyngeal anesthesia prior to transesophageal echocardiography tee. Differences in absorption and metabolism may explain the variability of benzocaine induced methemoglobinemia in these individuals. Although, as reported in the adult population, it happens most often due to prescribed medication or procedural anesthesia and not due to easily accessed overthecounter medications, the authors will describe an otherwise healthy male adult with no known. The topical anesthetic benzocaine is linked to a number of minor side effects, ranging from dry skin to allergies. Benzocaine and lidocaine induced methemoglobinemia after.
Acquired methemoglobinemia typically results from ingestion of specific drugs or agents that cause an increase in the production of methemoglobin. He developed central cyanosis and his oxygen saturation was 85% via pulse oximetry. Background fda data fdacommunication risk of methemoglobinemia in the medicine cabinet b patients need to know about benzocaine where too much of the hemoglobin in red. What is the prevalence of methemoglobinemia in the us. Virtual mentor ama journal of ethics american medical association.
Methemoglobinemia handbook of pediatric anesthesia. Then you can start reading kindle books on your smartphone, tablet, or computer no kindle device required. We report a case of methemoglobinemia secondary to selfadministered use of benzocaine spray. Collins portland veterans administration medical center and oregon health sciences university department of medicine, division of gastroenterology, portland, oregon topical 20% benzocaine hurricaine, beutlich, inc.
Sedation for gastrointestinal endoscopy 2008 thieme connect. Acute methemoglobinemia can be life threatening and usually is due to toxic exposure or drugs. In contrast, patients with hereditary methemoglobinemia are often asymptomatic despite the presence of cyanosis. Bevivino has developed methemoglobinemia, a rare adverse reaction to the benzocaine spray used to anesthetize her throat before the endoscopy. Few health care professionals realize that topical anesthetic spray can cause methemoglobinemia. When induced by benzocaine anesthetic spray and other chemicals, it can result in cyanosis and lifethreatening complications. Aug 31, 2015 methemoglobinemia is lifethreatening and bears pathognomonic signs difficult to diagnose in real time. Benzocaineinduced methemoglobinemia is an uncommon occurrence in clinical practice, and though few reports of benzocaineinduced methemoglobinemia are available in the englishlanguage cardiology literature, knowledge of this potentially lifethreatening condition is essential for clinicians performing routine procedures in which topically. Methemoglobin results from the presence of iron in the ferric form instead of the usual ferrous form. A serious but rare side effect of this overthecounter medication is a blood condition called methemoglobinemia. The most common causes of methemoglobinemia include oxidizing reactions to cocainederived anesthetics, such as benzocaine and lidocaine, to antibiotics, such as dapsone and other sulfonamides. Complications may include seizures and heart arrhythmias methemoglobinemia can be due to certain medications, chemicals, or food or it can be inherited from a persons. Acute methemoglobinemia can be lifethreatening and usually is acquired as a consequence of exposure to toxins or.
Topical benzocaine 20% hurricane spray used in egds gets absorbed and can cause methemoglobinemia. Therefore, obtaining a history of exposure to substances that can induce methemoglobinemia is important. Methemoglobinemia an overview sciencedirect topics. Methemoglobinemia caused by benzocaine topical spray yumpu. Few such reports of benzocaineinduced methemoglobinemia are available in the. Rebound methemoglobinemia benzocaine on mucous membranes with methemoglobin values as. Topical benzocaine associated with methemoglobinemia. Benzocaine has been reported to cause methemoglobinemia when applied to infants as an ointment or a rectal suppository 2, 3 and when used topically to the perineal area. The agent of choice depends on the method of administration, the. Severe methemoglobinemia complicating topical benzocaine use. Risk of acquired methemoglobinemia with different topical anesthetics during endoscopic procedures srikanth vallurupalli1, shalini manchanda21division of general internal medicine, department of medicine, southern illinois university school of medicine, springfield, il, usa. Methemoglobinemia should be considered in any patient who demonstrates cyanosis, respiratory distress, headache, lightheadedness, and a dark, chocolate. She required intubation, mechanical ventilation, and multiple doses of methylene blue for treatment. Methemoglobinemia secondary to lidocaine exposure is a relatively rare complication.
A high index of suspicion is needed for this readily treatable condition. Oxygen is carried through your bloodstream by hemoglobin, a protein thats attached to your red blood. Methemoglobinemia from topical benzocaine cleveland. A case is reported in which a patient developed methemoglobinemiainduced cyanosis while under general anesthesia during surgery for multiple fascial space infections. Methemoglobinemia caused by topical benzocaine guerriero. For this reason, the veterans health administration va announced on february 8, 2006, that they would stop using benzocainecontaining sprays for procedures involving the mouth and throat. Signs and symptoms of methemoglobinemia include cyanosis that doesnt respond to 100% oxygen therapy, a subnormal oxygenation saturation level by pulse oximetry, and muddy brown arterial blood that. Drugs implicated more often include local anesthetics benzocaine, lidocaine. Topical benzocaineinduced methemoglobinemia in the. A 27yearold woman was found to be in respiratory distress during postoperative recovery. Topical benzocaine is frequently applied to make the.
Benzocaine sprays, gels, and liquids, used as anesthesia during medical procedures and as a treatment for tooth and gum pain, have been associated with a serious and potentially fatal blood disorder called methemoglobinemia. Benzocaine induced methemoglobinemia pediatric research. Through march 16, 2011, a total of 21 cases of methemoglobinemia associated with the use of overthecounter benzocaine gel or liquid products were reported to the fdas adverse event reporting. Methemoglobinemia as a complication of 20% benzocaine spray. Neither patient had any evidence of pulmonary embolism or dvt or g6pd deficiency. Society for gastroenterology nurses and associates played a crucial role in the development of the. Reported adverse event cases of methemoglobinemia associated with benzocaine products. Methemoglobinemia mhb is characterized by abnormal levels of oxidized hemoglobin that cannot bind and transport oxygen. Benzocaine is a widely used topical anaesthetic and has been reported to cause toxic methaemoglobinaemia in otherwise healthy individuals with no predisposing risk factors.
Multisociety sedation curriculum for gastrointestinal endoscopy. Methylene blue intravenously is the treatment of choice to reduce methemoglobinemia. Pacelli,andkennethkatz department of emergency medicine, lehigh valley hospitalusf morsani college of medicine, cedar crest boulevard and. The fda notified healthcare professionals and patients that it has continued to receive reports of methemoglobinemia associated with benzocaine products. Abstractacute cyanosis and methemoglobinemia developed following topical application and partial ingestion of benzocaine for esophagogastroduodenoscopy. Rebound methemoglobinemia may occur up to 18 hours after mb administration, due to prolonged absorption of lipophilic agents benzocaine from adipose tissue. A standardized methemoglobinemia warning will also be added to prescription local anesthetics. Benzocaine cetacaine spray has been shown previously to cause methemoglobinemia in two patients when applied topically to the mucous membranes. Clinical symptoms may be observed at relatively low methemoglobin values, including coma at 32. Methemoglobinemia, betaglobin type, is a rare inherited disorder that disrupts the function of hemoglobin, the molecule in red blood cells that delivers oxygen throughout the body. Topical benzocaine hurricaine induced methemoglobinemia.
He developed central cyanosis and his oxygen saturation was 85% via pulse. Benzocaine, a commonly used topical anesthetic employed in multiple products, has been associated with methemoglobinemia. This isnt perfect, but it may provide some immediate information about the likelihood of severe methemoglobinemia. A 62yearold male underwent bronchoscopy where lidocaine oral solution and hurricaine spray 20% benzocaine were used. Pdf reported adverse event cases of methemoglobinemia. The failure of 100% oxygen to correct cyanosis is very suggestive of methemoglobinemia. Benzocaineinduced methemoglobinemiatwo case reports related. Patients with hereditary methemoglobinemia are asymptomatic despite the presence of cyanosis.
Methemoglobinemia clinical presentation british columbia. Benzocaine administration to facilitate upper endoscopic procedures can result in the relatively uncommon but potentially fatal complication known as methemoglobinemia. A 47yearold female with medical history of vulvar cancer and hiv undergoing chemoradiation was sent by the oncology. Side effects attributed to this agent are exceedingly rare. Hemoglobin is the protein in red blood cells rbcs that carries and distributes oxygen to the body.
Updated safety alert regarding benzocaineassociated. Enter your mobile number or email address below and well send you a link to download the free kindle app. Although, as reported in the adult population, it happens most often due to prescribed medication or procedural anesthesia and not due to easily accessed overthecounter medications, the authors will describe an otherwise healthy. Case report an atypical case of methemoglobinemia due to selfadministered benzocaine thomasm. Food and drug administration fda strengthened its warnings to the public about the potentially lifethreatening or lethal side effects that may occur with the use of benzocainecontaining products called methemoglobinemia. Topical benzocaine induced methemoglobinemia can occur in the pediatric population. Either arterial or venous blood may be used oxygen will be taken up from the atmosphere, thereby oxygenating the venous blood. Methemoglobinemia is a rare cause of hypoxemia, characterized by abnormal levels of oxidized hemoglobin that cannot bind to and transport oxygen. We describe a 56yearold woman who was transferred to our emergency department when severe cyanosis and chest pain developed after administration of topical oropharyngeal benzocaine and lidocaine during outpatient endoscopy. Case report an atypical case of methemoglobinemia due to self. Methemoglobinemia methb is a blood disorder in which an abnormal amount of methemoglobin is produced. Physicians should consider treating methemoglobinemia if the patient is symptomatic or the methemoglobin concentration rises to 30%.
Methemoglobinemia methba is a clinical syndrome caused by an increase in the blood levels of methemoglobin methb 1 secondary to both congenital chronic changes in hemoglobin hb synthesis or metabolism, or acute imbalances in reduction and oxidation reactions redox imbalance induced by the exposure to several chemical agents 2,3. Benzocaine and methemoglobinemia benzocaine is a local anesthetic commonly used as a topical pain reliever. Schug, hari krshnan, in side effects of drugs annual, 2010. Benzocaine overthecounter products can increase the risk of. Pulse oximetry readings will be inaccurate and not reflect the degree. Jun 04, 2018 any benzocaine products marketed to these patient populations will be removed from the market by fda.
Methemoglobinemia is a condition of elevated methemoglobin in the blood. A case is reported in which a patient developed methemoglobinemia induced cyanosis while under general anesthesia during surgery for multiple fascial space infections. Methemoglobinemia may occur as a result of medication overdoses or poisoning, but may also occur at standard doses. Reported adverse event cases of methemoglobinemia associated. Methemoglobinemia as a complication of 20% benzocaine. Inappropriate use of benzocaine sprays linked to risk for. Benzocaine induced methemoglobinemia is a rare complication associated with topical anesthesia and can be lifethreatening. This article reports on a rare case of benzocaineinduced methaemoglobinaemia following adenotonsillectomy in a 5yearold girl. Methemoglobinemia in a neonate with diarrhea pediatric. Acute methemoglobinemia may result from the use of several local anesthetic agents. Risk of serious and potentially fatal blood disorder prompts fda action on oral overthecounter benzocaine products used for teething and mouth pain and prescription local anesthetics.
Benzocaineinduced methemoglobinemia is a rare complication associated with topical anesthesia and can be lifethreatening. Topical anesthetics have been reported to cause methemoglobinemia, but this adverse event is extremely rare and has not been listed as one of the possible complications of tee. Acute methemoglobinemia after endoscopy american board. We describe a 4yearold girl who received a standard dose of topical benzocaine to her gastrostomy mucosa that resulted in rapid, severe methgb. Fna or interventions, preprocedural benzocaine spray of posterior. Benzocaine lawsuit methemoglobinemia lawyer, attorney, law firm. Although it occurs infrequently, benzocaineinduced methemoglobinemia is a potentially fatal complication if not promptly diagnosed and treated. Severe methemoglobinemia from topical anesthetic spray. Background methemoglobinemia mhb is characterized by abnormal levels of oxidized hemoglobin that cannot bind and transport oxygen. The color of the blood may be used to assess both the presence and severity of methemoglobinemia above.
For this reason, the veterans health administration va announced on february 8, 2006, that they would stop using benzocaine containing sprays for procedures involving the. Symptoms may include headache, dizziness, shortness of breath, nausea, poor muscle coordination, and bluecolored skin. Methods from 818 439 adverse event reports received by the us food and drug. We present a case of recurrent methemoglobinemia because of occult use of topical benzocaine to the vulva. Methemoglobinemia in a neonate with diarrhea pediatric oncall.
A diagnosis of acute toxic methemoglobinemia should be considered when cyanosis, with or without neurologic symptoms, occurs following the use of local anesthetics in the absence of cardiopulmonary disease. When induced by benzocaine anesthetic spray and other chemicals, it can result in. Acutely developing methemoglobinemia is infrequently. Methemoglobinemia is a blood disorder in which too little oxygen is delivered to your cells. Acquired methemoglobinemia is an uncommon hemoglobinopathy that results from exposure to oxidizing agents, such as chemicals or medications. Learn more about methemoglobinemia, betaglobin type, causes, symptoms, and genes. Methemoglobinemia and benzocaine article nursingcenter. Diagnosis methemoglobinemia should be considered in any patient who develops cyanosis after the use of topical pharyngeal anesthesia. Administration of low doses over prolonged periods may lead to chronic methemoglobinemia whereas large doses may lead to an. Benzocaine, sold under the brand name orajel amongst others, is an ester local anesthetic commonly used as a topical pain reliever or in cough drops. It should also be a suitable textbook for medical students, residents, nurses. Fda will continue to evaluate the risk of methemoglobinemia associated with benzocaine and provide updated information as necessary. The majority of reported cases of lidocaineinduced methemoglobinemia have been associated with upper airway or upper gastrointestinal procedures. We report a case of methemoglobinemia after topical use of benzocaine in.
Dec 09, 2018 methemoglobinemia congenital or acquired occurs when red blood cells rbcs contain methemoglobin at levels higher than 1%. Here we report a case of severe acquired methemoglobinemia resulting from topical use of benzocaine spray during diagnostic upper gastrointestinal. There should be high suspicion for methemoglobinemia in a cyanotic patient who has been exposed to any of the following. This results in a decreased availability of oxygen to the tissues. However, the ferrous iron has an increased affinity for bound. A single spray of benzocaine may induce methemoglobinemia. Methemoglobinemia congenital or acquired occurs when red blood cells rbcs contain methemoglobin at levels higher than 1%. The most common cause of congenital methemoglobinemia is cytochrome b5 reductase deficiency type ib5r. Local anesthetics are widely used and are known for eliciting this condition. The author reports one of these rare complications, druginduced methemoglobinemia, in a patient with methemoglobin reductase deficiency. Because of the lack of efficacy for teething and the serious safety concerns weve seen with overthecounter benzocaine oral health products, the. Risk of acquired methemoglobinemia with different topical. Dec 09, 2018 there is no evidence of cardiopulmonary disease.
1597 940 583 854 1174 989 1017 463 1414 829 503 1037 230 294 1038 254 682 1250 816 1169 150 1613 65 992 69 810 1095 242 393 481 326 384 143 408 400 885 477 1147 629 524 958 251 72 847 1119 1435 1325 227 1211 223