What is the treatment for a 14-year-old with a diphenhydramine (Benadryl) overdose?

From the Guidelines

The treatment for a 14-year-old with a diphenhydramine (Benadryl) overdose requires immediate medical attention at an emergency department, with a focus on supportive care to manage airway, breathing, and circulation, as well as cardiac monitoring and treatment of severe anticholinergic symptoms. The initial management includes activated charcoal administration if the ingestion occurred within 1-2 hours and the patient is alert 1.

Key Considerations

• Supportive care is the mainstay of treatment, focusing on maintaining airway, breathing, and circulation.
• Intravenous fluids should be given to prevent hypotension, and cardiac monitoring is essential due to potential arrhythmias.
• For severe anticholinergic symptoms (confusion, hallucinations, hyperthermia), physostigmine may be considered at 0.02 mg/kg IV (maximum 2 mg) under careful monitoring, though this is reserved for severe cases without QRS prolongation.
• Benzodiazepines such as lorazepam 0.05-0.1 mg/kg IV may be used for agitation or seizures.
• Cooling measures should be implemented for hyperthermia. It's worth noting that the provided evidence primarily discusses benzodiazepine overdose, which is different from diphenhydramine overdose, but the general principles of supportive care and management of symptoms apply 1.

Additional Measures

• Monitoring for potential complications, such as respiratory depression, cardiac arrhythmias, and seizures, is crucial.
• The patient's vital signs and mental status should be closely monitored, and any changes should be addressed promptly. Diphenhydramine overdose can cause anticholinergic toxicity affecting multiple body systems, including the central nervous system and cardiovascular system, which explains the varied symptoms and need for comprehensive supportive care 1. Most patients recover completely with appropriate treatment within 24-48 hours.

From the FDA Drug Label

In case of accidental overdose, get medical help or contact a Poison Control Center right away (1-800-222-1222) The treatment for a 14-year-old with a diphenhydramine (Benadryl) overdose is to get medical help or contact a Poison Control Center right away by calling 1-800-222-1222 2.

From the Research

Treatment Overview

The treatment for a 14-year-old with a diphenhydramine (Benadryl) overdose involves several steps, including assessment, referral to an emergency department if necessary, and administration of specific treatments. According to 3, patients with suicidal intent, intentional abuse, or suspected malicious intent should be referred to an emergency department.

Assessment and Referral

• Patients experiencing changes in behavior, such as agitation, staring spells, or hallucinations, should be referred to an emergency department 3.
• Children less than 6 years of age who ingest at least 7.5 mg/kg of diphenhydramine should be referred to an emergency department 3.
• Patients 6 years of age and older who ingest at least 7.5 mg/kg or 300 mg of diphenhydramine (whichever is less) should be referred to an emergency department 3.

Treatment Options

• Intravenous sodium bicarbonate may be administered by EMS personnel if QRS widening (QRS >0.10 msec) is present and if authorized by EMS medical direction 3.
• Physostigmine should be reserved for administration in a hospital 3.
• Benzodiazepines may be administered by EMS personnel if agitation or seizures are present, and if authorized by EMS medical direction 3.
• Sodium bicarbonate has been shown to be effective in treating diphenhydramine overdose by reversing sodium channel blockade 4, 5.
• Donepezil has been used as an unusual therapy for acute diphenhydramine overdose, improving the patient's level of consciousness and regressing anticholinergic features 6.

Management

• Patients with acute ingestions of less than a toxic dose of diphenhydramine, or chronic exposures to diphenhydramine and no or mild symptoms, can be observed at home with instructions to call the poison center back if symptoms develop or worsen 3.
• The poison center should consider making a follow-up call at approximately 4 hours after ingestion 3.