From the Guidelines
Fatal cyproheptadine poisoning requires immediate medical attention, with treatment focusing on supportive care, including gastric decontamination, maintaining airway, breathing, and circulation, and managing symptoms such as seizures, hyperthermia, and cardiac issues. The treatment approach is largely based on the management of serotonin syndrome, as cyproheptadine is used as a serotonin2A antagonist in such cases 1. According to the provided evidence, treatment often involves discontinuing the precipitating agent and providing supportive care, which may include treatment of agitation with benzodiazepines, amelioration of hyperthermia, and management of autonomic instability 1.
Key considerations in managing cyproheptadine poisoning include:
- Gastric decontamination with activated charcoal if the patient presents within 1-2 hours of ingestion
- Supportive care to maintain airway, breathing, and circulation
- IV fluids for hypotension
- Benzodiazepines for seizures, such as lorazepam 2-4 mg IV or diazepam 5-10 mg IV
- Cooling measures for hyperthermia
- Cardiac monitoring
It's crucial to monitor patients with significant ingestions in an intensive care setting for at least 24 hours, as symptoms can progress rapidly and complications may develop even after initial stabilization 1. The dosage of cyproheptadine for therapeutic use is typically 12 to 24 mg over 24 hours, but in cases of poisoning, much higher doses can lead to severe toxicity, including respiratory depression, coma, and cardiovascular collapse 1.
Given the potential for severe morbidity and mortality associated with cyproheptadine poisoning, a cautious approach with immediate medical intervention and close monitoring is essential to prevent fatal outcomes. The evidence highlights the importance of recognizing the clinical presentation of serotonin syndrome and other drug toxicity syndromes, as prompt and appropriate treatment can significantly impact patient outcomes 1.
From the Research
Fatal Cyproheptadine Poisoning
- Cyproheptadine is a serotonin and histamine antagonist that can cause anticholinergic syndrome, characterized by symptoms such as agitation, confusion, and hallucinations 2.
- In cases of anticholinergic poisoning, physostigmine can be a useful antidote, but its use is not without risks, including seizures and cardiac arrhythmia 3.
- Cyproheptadine overdose can be fatal, as evidenced by a case report of a 28-year-old man who died from ethanol and cyproheptadine intoxication 4.
- The toxicity of cyproheptadine has been evaluated in 113 cases of accidental ingestion by children, with symptoms including somnolence, excitation, hallucinations, and tachycardia, but no life-threatening alterations were observed at doses ranging from 0.3-6.15 mg per kg of body weight 5.
- A retrospective review of cases reported to the California Poison Control System found that cyproheptadine was not effective in reducing serious outcomes or hospitalization rates in patients with serotonin syndrome, and its use was associated with a higher risk of intubation and critical care unit admission 6.