Cyanosis and methemoglobinemia

DOT CLASSIFICATION 6.1 Label Poison SAFETY PROFILE Poison by ingestion, intravenous, and intraperitoneal routes. Moderately toxic by intramuscular route. Mutation data reported. Acute symptoms of exposure are headache, nausea, vomiting, weakness and stupor, cyanosis and methemoglobinemia. Chronic exposure can cause liver damage. Experimental reproductive effects. Combustible when exposed to heat or flame. See NITRATES for explosion and disaster hazards. To fight fire, use water spray or mist, foam, dry chemical, CO2. Vigorous reaction with sulfuric acid above 200°C. Reaction with sodium hydroxide at 130°C under pressure may produce the explosive sodium-4-nitrophenoxide. When heated to decomposition it emits toxic fumes of NOx. See also m-NITROANILINE, o-NITROANILINE, NITRO COMPOUNDS OF AROMATIC HYDROCARBONS, and ANILINE DYES. 

Chronic effects in workers exposed to o-toluidine include anemia, anorexia, weight loss, skin lesions, central nervous system depression, cyanosis, and methemoglobinemia. o-Toluidine and p-toluidine are suspected carcinogens (bladder cancer). 

No data are available to reliably estimate the level of human oral exposure to nitrobenzene that results in methemoglobinemia. Two of the case studies that were located indicate that some vague quantity, such as a few drops or a partial spoonful, was swallowed and part of that amount was vomited out before cyanosis and methemoglobinemia were observed (Carter 1936 Leader 1932). Another study (Myslak et al. 1971) estimated that a dose of 4.3 to 11 g was swallowed by a 19-year-old woman, based on the urinary levels of p-nitrophenol. 

In a 17-day-old and a 7-month-old child cyanosis and methemoglobinemia developed after subcutaneous application of prilocaine for circumcision [74 ]. 

Continuous exposure of rats by inhalation to 0.0055 and 0.3mg/m for 100 days resulted in methemoglobinemia, lowered erythrocyte hemoglobin, leukopenia and reticulocytosis, and reduced muscle chronaxie. Doses up to 500mg/kg administered by gavage to rats and mice for 13 weeks caused cyanosis and decreased motor activity, as well as hemosiderosis in the spleen liver, kidney, and testes. Bone marrow hyperplasia was observed in rats, and mice had increased hematopoiesis in the liver. In general, all toxic effects could be attributed to chronic methemoglobinemia, erythrocyte destruction, and erythrophagocytosis. 

Methemoglobinemia. The presence of methemoglobin in the blood, resulting in cyanosis and headache, dizziness, fatigue, ataxia, dyspnea, tachycardia, nausea, vomiting, drowsiness, stupor, coma, and sometimes death. 

Sax (Ref 14) considers the DNTs to be highly poisonous. They can be absorbed by the skin or inhaled causing anemia, methemoglobinemia, cyanosis and liver damage. The threshold tolerance level is 1.5mg/m3 of air. They are considered to be a moderate fire and expln hazard (Ref 23)... 

Causes conjunctivitis, corneal opacities, irritation of skin and blistering, nausea, vomiting, jaundice, anemia, diarrhea, cyanosis, liver toxicity, and methemoglobinemia.4,5 Animal carcinogen. Reasonably anticipated to be a human carcinogen. LD50 (oral, human) 50 mg/kg LD50 (oral, rat) 500 mg/kg.3... 

DOT CLASSIFICATION 6.1 Label ICEEP AWAY FROM FOOD SAFETY PROFILE Poison by ingestion, subcutaneous, and intraperitoneal routes. An experimental teratogen. Other experimental reproductive effects. An allergen and skin and eye irritant. Mutation data reported. Can cause contact dermatitis, bronchial asthma, and methemoglobinemia with cyanosis. When heated to decomposition it emits toxic fumes of NOx. 

Cetacaine spray used to anesthetize the oropharjmx before endoscopy led to dyspnea, central cyanosis, and an oxygen saturation of 80% methemoglobinemia was diagnosed, and the patient recovered... 

Flutamide can cause methemoglobinemia (6-8) or sulfhemoglobinemia (5). The latter occurred in a 70-year-old man who had taken flutamide 150 mg tds for 1 month and developed cyanosis and anemia that was not responsive to methylthioninium chloride (methylene blue). 

In eight episodes of toxic methemoglobinemia in seven premature infants after the combination of caudal anesthesia (prilocaine 5.4—6.7 mg/kg) and Emla cream (prilocaine 12.5 mg) for herniotomy, the highest methe-moglobin concentration 5.5 hours after anesthesia was 31% (86). All the infants were sjmptomatic, with mottled skin, pallor, cyanosis, and poor peripheral perfusion. The most severe symptoms occurred at 3-8 hours and disappeared within 10-20 hours. The authors stressed the importance of recognizing the poor tolerance of premature infants to methemoglobinemia and that whereas topical prilocaine is relatively safe, caudal administration is not. 

Adverse effects that have been reported following irrigation of hydatid cysts with cetrimide solution include chemical peritonitis, methemoglobinemia with cyanosis, and metabolic disorders. ... 

Both amyl nitrite and sodium nitrite oxidize the ferrous iron in hemoglobin, creating measurable levels of methemoglobin. Patients receiving sodium nitrite infusions require close require constant monitoring of blood pressure and close observation for cyanosis and shock, both manifestations of methemoglobinemia. 

Prilocaine is an amide-type LA, with a very low allergenic potential and low toxicity" and is non-vasodilating. Unfortunately, prilocaine is metabolized into ortho-toluidine, a chemical that can induce methemoglobinemia. In doses higher than 500 mg, it can cause cyanosis and reduce the oxygen-carrying capacity of the blood. 

Methemoglobinemia is a rare occurrence with nitrate therapy and is characterized by cyanosis, and nausea/vomiting, progressing to shock and coma. This rare adverse effect is usually associated with high doses/overdoses of nitrate products, but can also be seen at normal therapeutic doses. 

The acute oral toxicity was moderate to high in test animals. It produced methemoglobinemia, cyanosis, and anemia. The oral LD50 value in rats is 250-300 mg/kg. It is a mild skin irritant. The irritation effect on rabbits eyes was moderate. 

The acute oral toxicity of resorcinol is moderate in most test animals. It is less toxic than phenol or catechol. Ingestion or skin absorption can cause methemoglobinemia, cyanosis, and convulsions. Vapors or dusts are irritant to mucous membranes. Contact with the skin or eyes can cause strong irritation. An amount of 100 mg caused severe irritation in rabbit eyes. 

A. Methemoglobinemia (see p 261) causes cyanosis and dyspnea. Drawn blood may appear dark chocolate brown when the methemoglobin level is... 

A case series of methemoglobinemia with respiratory distress, cyanosis, and tachycardia, was reported in four infants, 7 to 9 months old, that had been fed purees of fennel (part and dose used not specified). High nitrate levels in the products administered were believed to be responsible for the methemoglobinemia (Murone et al. 2005). 

Toxicology TDLo (oral, wmn) 600 mg/kg ing. of 20-40 g in adults has produced dizziness, nausea, methemoglobinemia with cyanosis and hypotension... 

The symptoms of methemoglobinemia can easily be predicted from this brief description of the properties of methemoglobin. A moderate methemo obine-mia induces dyspnea, cyanosis, and compensatory polycythemia. 

An otherwise healthy 32-year-old woman received prilocaine 60 mg for removal of a gluteal abscess and developed symptoms of suspected methemoglobinemia, with dizziness, fever, and headache 1 hour after surgery and peripheral cyanosis and tachycardia 3 hours later [75 ]. She was given 5 ml of methylthioninium chloride 1% and her symptoms resolved within 30 minutes. Erythrocyte glucose-6-phosphate-dehydrogenase activity was normal. 

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