Promethazine is NOT Recommended for Ethanol Overdose
Promethazine (a phenothiazine antihistamine) has no role in the treatment of ethanol overdose and should not be used. There is no evidence supporting its use, and it may worsen outcomes by adding sedation and anticholinergic effects to an already CNS-depressed patient.
Standard Management of Ethanol Overdose
The treatment of acute ethanol poisoning consists exclusively of supportive care—there are presently no agents available for clinical use that will reverse the acute effects of ethanol 1.
Immediate Priorities
Airway protection and respiratory support: Establish and maintain airway patency with bag-mask ventilation if needed, progressing to endotracheal intubation for patients unable to protect their airway 2. Ethanol causes respiratory depression that can be fatal, particularly at blood alcohol concentrations >250 mg/dL 1.
Cardiovascular stabilization: Support breathing and oxygenation to prevent hypoxemia-related tissue injury, and treat hypotension with standard fluid resuscitation and vasopressors as indicated 2.
Thiamine before dextrose: Administer thiamine (vitamin B1) followed by dextrose to prevent Wernicke encephalopathy 1.
Measure blood alcohol concentration: Obtain levels to guide prognosis and duration of monitoring 1.
Supportive Care Protocol
Treatment consists of close observation until the blood alcohol concentration decreases to a non-toxic level 1. In non-dependent adults, ethanol is metabolized at approximately 15 mg%/hour 1.
When to Consider Hemodialysis
Hemodialysis may be considered in cases of a severely ill child or comatose adult 1. This is reserved for life-threatening presentations with profound CNS depression and respiratory failure 3.
Critical Pitfalls to Avoid
Do not use promethazine or other sedating medications: Adding phenothiazines, benzodiazepines (unless treating withdrawal), or other CNS depressants will compound respiratory depression.
Always evaluate for co-ingestions: Co-ingestions significantly increase morbidity and mortality risk, particularly with opioids, benzodiazepines, and other CNS depressants 2. Administer naloxone immediately if opioid co-ingestion is suspected 2.
Consider alternative diagnoses: After stabilization, evaluate for other causes of altered mental status beyond ethanol alone 1.
Special Populations
Children and alcohol-naive adults: May experience severe toxicity at blood alcohol concentrations <100 mg%, whereas chronic alcoholics may demonstrate significant impairment only at concentrations >300 mg% 1.
Ethanol-dependent patients: Monitor for withdrawal syndrome, which may occur within 8 hours of the last drink even with blood alcohol concentrations >200 mg% 1.
Poison Control Consultation
Contact the regional poison center for expert toxicology guidance on complex cases, as these centers are staffed by board-certified medical and clinical toxicologists 2.