From the Guidelines
Strychnine poisoning requires immediate medical attention, with treatment focusing on airway management, seizure control, and supportive care, as outlined in the most recent guidelines from the American Heart Association 1.
Key Considerations
- Symptoms of strychnine poisoning include severe muscle spasms, rigidity, and painful convulsions that can be triggered by minor stimuli, with the victim remaining conscious and in extreme pain.
- Benzodiazepines like diazepam (5-10mg IV) or midazolam are first-line treatments for controlling convulsions, often requiring high doses, as supported by the American Heart Association guidelines 1.
- Muscle relaxants such as vecuronium may be needed in severe cases, necessitating intubation and mechanical ventilation.
- Activated charcoal (1g/kg orally) can help if administered within 1-2 hours of ingestion, as part of the supportive care measures.
- Maintaining a quiet, dark environment is crucial to minimize stimuli that trigger convulsions, and acidification of urine with ammonium chloride may enhance strychnine elimination.
Treatment Approach
- The lethal dose for adults is approximately 50-100mg, though deaths have occurred with as little as 15mg, highlighting the importance of prompt and effective treatment.
- Prognosis depends on the amount ingested, time to treatment, and quality of supportive care, with complete recovery possible if the patient survives the acute phase, as strychnine does not cause permanent organ damage.
- The American Heart Association guidelines emphasize the importance of supportive care, including airway management, hemodynamic support, and correction of critical vital sign and metabolic derangements, in the treatment of critically poisoned patients 1.
Recommendations
- Immediate medical attention is crucial in cases of strychnine poisoning, with a focus on airway management, seizure control, and supportive care.
- Benzodiazepines and muscle relaxants should be used as first-line treatments for controlling convulsions and muscle spasms.
- Activated charcoal and acidification of urine with ammonium chloride may be useful in reducing strychnine absorption and enhancing elimination.
- Maintaining a quiet, dark environment is essential to minimize stimuli that trigger convulsions, as supported by the American Heart Association guidelines 1.
From the Research
Symptoms of Strychnine Poisoning
- Severe tonic-clonic seizures and tetanus-like contractions while the patient is fully conscious 2
- Hyperreflexia, severe muscle spasms, and convulsions due to competition with the inhibitory neurotransmitter glycine 3
- Respiratory failure, leading to death if left untreated 2
- Metabolic acidosis, hyperthermia, and rhabdomyolysis with renal failure 2
Treatment of Strychnine Poisoning
- Aggressive airway control and treatment of seizures with benzodiazepines or barbiturates 4
- Neuromuscular blockade may be required to control convulsions 4, 5
- Gastric lavage with water, oral administration of activated charcoal and sorbitol solution, and hemodialysis for acute renal failure may be necessary 6
- Early aggressive treatment, including intubation and cardiac massage, can be life-saving 2, 5
Diagnosis of Strychnine Poisoning
- Confirmation of strychnine poisoning is best obtained by submitting urine or gastric aspirate for analysis utilizing a qualitative test such as thin layer chromatography (TLC) 4
- Gas chromatography-mass spectrometry can also be used to confirm the presence of strychnine in urine or blood specimens 5, 3
Prognosis of Strychnine Poisoning
- Recovery from strychnine poisoning is usually complete and rapid if treatment is aggressive 4
- Fatal outcome can occur if treatment is delayed or inadequate 6, 5
- Patients who receive early and aggressive treatment may have favorable outcomes, even if they have ingested a normally fatal amount of strychnine 6