Anticholinergic toxicity from lupin bean consumption: a case series

Introduction Lupin beans, or termos, are part of the legume family closest to peas. They are popular snacks in the Mediterranean region, a high protein source, and traditional home remedies for diabetes, weight loss, and arthritis. Few cases of anticholinergic toxicity have been reported worldwide due to poor preparation of bitter lupin varieties containing high concentrations of alkaloids.Case series We describe six patients who consumed improperly cooked lupin beans or lupin-soaked water and had different presentations, grouped under anticholinergic toxicity. These cases were managed at the emergency department between September 2023 and December 2024. They were given supportive treatment with symptom resolution after a maximum of 24 h. The improper method of preparation of lupin for each case was highlighted.Conclusion Bitter lupins, which are common in the Mediterranean region, contain primarily sparteine, an alkaloid that imparts the bitter taste and causes anticholinergic toxicity. Symptoms can vary between individuals, ranging from mild to severe anticholinergic symptoms. Diagnosis necessitates meticulous medical history and clinical suspicion, as symptoms can mimic other conditions. Raising awareness among emergency physicians is crucial in regions with high lupin consumption. Public education on proper debittering through prolonged water soaking for up to 5 days may reduce toxicity.