The jequirity pea (Abrus precatorius) and castor bean (Ricinus communis) belong to a family of poisonous plants that contain toxalbumins. The chief toxin of the jequirity pea is abrin, which is structurally very similar to the toxin ricin of the castor bean. Ingestion of jequirity peas and castor beans rarely results in toxicity, as most of the plant toxin is concentrated within the hard shell of the seeds. However, when these seeds are chewed or the shell is digested, symptoms of severe gastroenteritis follow within 1 to 3 days. Nausea, vomiting, abdominal pain, and diarrhea are common but, in severe cases, may be accompanied by hemorrhagic gastritis and hematemesis, seizures, arrhythmias, marked dehydration, CNS depression, and even death. Unfortunately, because of the colorful attractive nature of jequirity peas and castor beans, most cases of ingestion occur in the pediatric age group. Because of the very high potency of these toxins, they are occasionally used for homicidal purposes, and growing concern exists for their potential utilization as an agent of bioterrorism.
Management and Disposition
Treatment of jequirity pea and castor bean ingestions is largely supportive, as there is no specific antidote for abrin or ricin. Gastric decontamination may be considered and may include activated charcoal and whole-bowel irrigation. In asymptomatic patients, decontamination, careful observation, and close follow-up are adequate. With symptoms of toxicity, however, admission is recommended, as the potential for marked clinical worsening is present.
Castor Bean Plant. The castor bean plant is large and leafy; it may reach a height of 10 to 12 ft. (Photo contributor: Alex Wilson.)
Most jequirity pea and castor bean ingestions are benign, as the vast majority of toxin resides within the undigested shell of the plant.
The toxalbumins abrin and ricin are structurally similar to botulinum toxin, cholera toxin, diphtheria toxin, and insulin.
Severe allergic reactions with anaphylaxis have been reported with handling of the seeds of castor bean and are also seen among workers in factories where castor oil is produced.
The castor bean plant is commercially cultivated as a source of castor oil. Such oil has been used for centuries as a purgative and as a lubricant for machines.
Castor Bean. Typical appearance of the castor bean. (Photo contributor: Alex Wilson.)
Jequirity Pea. Jequirity peas are also known as rosary peas, Indian beans, Buddhist’s beads, crab’s eyes, and prayer beads. They are about 5 mm in diameter and have a colorful glossy shell, usually red with a black center, although black and white may also be seen. (Photo contributor: Kevin J. Knoop, MD, MS.)