UMEM Educational Pearls


What is the name of the toxin found in this seed/bean and its mechanism of toxicity?



Name: Jequirity bean or rosary pea (Abrius precatorius)

Toxin: Abrin (toxalbumin)

Mechanism of toxicity: 

  • Abrin is a toxin that is similar to ricin in structure and mechanism.
  • It is a dimer with A and B-chains.
  • B-chain facilitates entry into the cell (via endocytosis)
  • A-chain inhibit protein synthesis by inhibition of ribosome 60S


  • Ingestion (most common): The bean/pea must be chewed or grinded, which releases Abrin, to cause toxicity. Whole bean/pea ingestion without breaking its shell is non-toxic
  • Injection (rare): potentially life-threatening.

Signs and symptoms of toxicity:

  • GI: nausea, vomiting, abdominal pain, diarrhea (common) --> electrolyte abnormalities, hypovolemia, GI bleeding
  • Severe toxicity: multiorgan failure, hypovolemic shock and death.


  • Predominantly supportive measures/care. 
  • There is no “antidote” for Abrin or Ricin toxicity.



  1. Audi et al. Ricin poisoning: A comprehensive review. JAMA 2005 Nov 9;294(18):2342-51.
  2. Rinner GR et al. Fatal abrin poisoning by injection. CLin Toxicol (Phila). 2020 June 1;1-3. doi: 10.1080/15563650.2020.1771360.


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