Prehospital and Emergency Department Care
Prehospital care
Prehospital management includes gathering evidence of ingestion, administration of charcoal in alert patients with an exposure of more than 5 mg of thyroxine, a full initial assessment, oxygen, and intravenous access as necessary.
Emergency department care
If the ingestion is 0.5 mg (500 mcg) or less, discharge the patient home because no gastric decontamination is indicated. [5]
Most unintentional exposures can be treated with no decontamination, prudent follow up and observation at home, especially if calculated dose is below 4 mg (4,000 mcg). [6] Virtual or telephonic follow up should be conducted up to 10 days after exposure.
Unintentional exposures in excess of 5 mg (5,000 mcg) of thyroxine may benefit from administration of activated charcoal.
Intentional massive exposures in excess of 10 mg (10,000 mcg) that present early (within an hour) may benefit from more aggressive decontamination, including gastric lavage, and subsequent administration of activated charcoal.
Patients with massive exposures or ingestion of T3-containing preparations should be admitted in anticipation of pending toxicity.
Admit all symptomatic patients and place them on cardiac monitoring. Symptomatic patients require correction of dehydration and control of hyperthermia.
Important treatment points include the following:
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Ipecac syrup is no longer recommended for home or hospital treatment.
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Asymptomatic patients should not be treated empirically with beta-blockers.
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Chronic overdose—withdraw drug.
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Use acetaminophen for fever control; aspirin is contraindicated because it displaces T4 from thyroid-binding globulin (TBG), increasing free T4.
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Because of the delayed conversion to T3 and distribution to tissues, patients must be observed and managed for a longer period of time, especially with large overdoses.
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The hypothalamic-pituitary-thyroid axis will return to normal in 6-8 weeks.
Consultations
Consult the regional poison control center or local medical toxicologist (certified through the American Board of Medical Toxicology or the American Board of Emergency Medicine) for additional information and patient care recommendations.
Further inpatient care
Inpatient admission is warranted for symptomatic patients. Because symptoms generally revolve around cardiovascular manifestations of thyrotoxicosis, admit to a cardiac monitored bed while appropriate beta-blockade, IV hydration, and control of agitation and hyperthermia are achieved.
Inpatient and outpatient medications
Patients most frequently are treated on an outpatient basis if good follow-up can be guaranteed and psychiatric evaluation is not required. When symptoms develop, beta-blockade may be initiated and titrated to response.