Methanol Toxicity

Initiate resuscitation and toxic alcohol treatment when a patient has a compatible ingestion or exposure plus unexplained metabolic acidosis, visual disturbance, or a combined osmolar and anion gap. Methanol is found in some cleaning products, antifreeze-related products, illicit or contaminated alcoholic beverages, and contaminated hand sanitizers. Ingestion is the usual route, but inhalational and dermal poisonings are reported rarely. fda+3fdaFDA updates on hand sanitizers consumers should not use | FDANatureMethanol toxicity; characteristics, ophthalmological sequelae and recommended treatment | Eyejournal chestnetVomiting, Abdominal Pain, and Visual Disturbances in a 31-Year ...PubMedAmerican Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning - PubMed

Obtain airway and ventilatory support when mental status or respiratory compensation is failing. Severe methanol poisoning can progress from nausea, vomiting, headache, dizziness, and ataxia to seizures, coma, permanent neurologic injury, blindness, and death. A latent interval of approximately 12 to 24 hours may precede uncompensated acidosis and visual dysfunction; concurrent ethanol can delay this evolution. fda+2fdaFDA updates on hand sanitizers consumers should not use | FDAjournal chestnetAdult Toxicology in Critical Carea - CHEST JournalPubMedAmerican Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning - PubMed

Contact a poison center or medical toxicologist while drawing diagnostic studies, but administer an alcohol dehydrogenase inhibitor without waiting for a methanol result when suspicion is strong. Early blocking-agent administration is time-sensitive because toxicity results from metabolic conversion to formic acid rather than from methanol alone. NEJM+2NEJMFomepizole for the Treatment of Methanol PoisoningCDCMedical Management Guidelines for Ethylene Glycol - cdc.gov.PubMedAmerican Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning - PubMed

Obtain basic metabolic panel with calculated anion gap, measured serum osmolality with calculated osmolarity, venous or arterial blood gas, ethanol concentration, and a quantitative methanol concentration where locally available. Anion gap and bicarbonate are an adequate initial screen for most acid-base disorders, while blood gas testing defines acidemia and respiratory compensation. Oxford AcademicOxford AcademicLaboratory Recognition and Testing in Acid-Base Disorders

The diagnostic pattern changes as methanol is metabolized. Parent methanol increases the osmolar gap; formate increases the anion gap. In one series, both anion and osmolar gaps were elevated in 11 of 11 patients, but neither gap should be used as an exclusion test in isolation. Oxford Academic+1Oxford AcademicIncreased Serum Formate in the Diagnosis of Methanol Poisoningjournal chestnetATYPICAL PRESENTATION OF SEVERE METHANOL POISONING ...

A high osmolar gap with little acidosis can reflect earlier presentation before substantial formate generation, whereas high-anion-gap acidosis with a lower osmolar gap can reflect later presentation after parent methanol has been consumed. Concurrent ethanol competitively inhibits metabolism and may prolong the latent period and alter the expected laboratory trajectory. Nature+2NatureToxic Alcohol Poisoning and Metabolic Acidosis | Toxicology - NatureScienceDirectMethanol Half-Life During Ethanol Administration: Implications for Management of Methanol Poisoning - ScienceDirectPubMedAmerican Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning - PubMed

Interpret an elevated lactate cautiously in suspected toxic alcohol poisoning. Methanol or ethylene glycol can produce an osmolar gap plus anion-gap acidosis, and reported high lactate values may be analytically misleading in this setting. If the clinical pattern remains discordant, prioritize serial pH, bicarbonate, anion gap, osmolar gap, and direct methanol or formate testing rather than excluding toxic alcohol poisoning from a single lactate result. NEJM+1NEJM118 Readers' Comments - The New England Journal of MedicineNatureToxic Alcohol Poisoning and Metabolic Acidosis | Toxicology - Nature

Use fomepizole as the preferred alcohol dehydrogenase inhibitor when available. The cited regimen is 15 mg/kg IV loading dose, followed 12 hours later by 10 mg/kg IV every 12 hours for four doses, then 15 mg/kg IV every 12 hours as long as treatment is required. Fomepizole has low toxicity and is easier to administer than ethanol; it is FDA-approved for methanol and ethylene glycol poisoning. CDC+1CDCMedical Management Guidelines for Ethylene Glycol - cdc.gov.WHO[PDF] The Selection and Use of Essential Medicines - IRIS

If fomepizole is unavailable, use ethanol to competitively inhibit alcohol dehydrogenase. Target a blood ethanol concentration of 100 to 150 mg/dL. The cited IV ethanol loading dose is 600 to 800 mg/kg; maintenance dosing depends on chronic alcohol use and must be increased during hemodialysis. CDCCDC[PDF] Ethylene/Propylene Glycol Toxicity - CDC Stacks

Give intravenous sodium bicarbonate for significant metabolic acidosis or ophthalmologic abnormalities. Formic acid is central to the acidosis and ocular injury of methanol poisoning, and correction of acidemia is specifically recommended in patients with significant acidosis or ophthalmologic findings. PubMedPubMedAmerican Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning - PubMed

Use folinic acid as an adjunct in severe methanol poisoning protocols, particularly when formate toxicity is present, but do not substitute it for antidotal blockade, bicarbonate, or extracorporeal removal when indicated. Recommended treatment descriptions include fomepizole or ethanol, folinic acid, sodium bicarbonate, and hemodialysis. Nature+1NatureMethanol toxicity; characteristics, ophthalmological sequelae and recommended treatment | EyeWHO[PDF] the national protocol for treatment of substance use disorders in ...

Use intermittent hemodialysis as an adjunct to alcohol dehydrogenase blockade for severe acidosis, renal dysfunction, or clinically significant toxicity. Hemodialysis removes parent compounds and metabolites and is a key escalation treatment when acid-base derangements or organ toxicity are substantial. Nature+1NatureToxic Alcohol Poisoning and Metabolic Acidosis | Toxicology - NatureCDCMedical Management Guidelines for Ethylene Glycol - cdc.gov.

A serum methanol concentration above 50 mg/dL has historically been used as a hemodialysis threshold; one cited guideline summary recommends dialysis above 15.6 mmol/L (50 mg/dL) until the concentration is below 6.25 mmol/L. However, more recent guidance summarized in the literature does not require dialysis solely because the level exceeds 50 mg/dL if the patient is receiving fomepizole or ethanol, remains asymptomatic, has normal arterial pH, and has no other dialysis indication. ScienceDirect+1ScienceDirectEthylene Glycol Elimination Kinetics and Outcomes in Patients Managed Without Hemodialysis - ScienceDirectKidney InternationalPrediction and validation of hemodialysis duration in acute methanol ...

Continue serial clinical and metabolic assessment during antidote therapy and dialysis: visual and neurologic status, pH, bicarbonate, anion gap, osmolar gap, and quantitative methanol when available. Persistent or worsening acidosis, new visual dysfunction, coma, seizures, or renal dysfunction should be managed as treatment failure requiring urgent extracorporeal escalation or continuation. fda+3fdaFDA updates on hand sanitizers consumers should not use | FDANatureToxic Alcohol Poisoning and Metabolic Acidosis | Toxicology - NatureCDCMedical Management Guidelines for Ethylene Glycol - cdc.gov.PubMedAmerican Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning - PubMed

Admit patients receiving fomepizole, ethanol infusion, or hemodialysis to an ICU-level setting. Observe for delayed organ injury and maintain a low threshold for repeat renal and metabolic testing when the presentation could instead represent ethylene glycol exposure, in which renal effects often develop 24 to 72 hours after ingestion. CDCCDCMedical Management Guidelines for Ethylene Glycol - cdc.gov.

Treat ingestion of hand sanitizer labeled as ethanol but potentially contaminated with methanol as a toxic alcohol exposure. FDA has identified products testing positive for methanol despite ethanol labeling; methanol is not an acceptable ingredient in drug products, and substantial exposure can cause blindness, seizures, coma, permanent neurologic damage, or death. fdafdaFDA updates on hand sanitizers consumers should not use | FDA

Ask whether multiple persons consumed the same alcohol product or whether a household, workplace, or shelter shares the implicated product. Methanol outbreaks have occurred after contaminated or adulterated alcoholic beverages, and early source identification can direct evaluation of additional exposed persons before they develop delayed acidosis or visual toxicity. Nature+1NatureMethanol toxicity; characteristics, ophthalmological sequelae and recommended treatment | EyePubMedAmerican Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning - PubMed

Remove the suspected product from further use and preserve the container for public health or toxicologic identification when feasible. Dermal absorption has been reported, but children who ingest sanitizer and adults who consume it as an ethanol substitute are at particularly high risk for life-threatening poisoning. fda+1fdaFDA updates on hand sanitizers consumers should not use | FDAPubMedAmerican Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning - PubMed