Black henbane and its toxicity - a descriptive review

Black henbane (BH) or Hyoscyamus niger, has been used as a medicine since last centuries and has been described in all traditional medicines. It applies as a herbal medicine, but may induce intoxication accidentally or intentionally. All part of BH including leaves, seeds and roots contain some alkaloids such as Hyoscyamine, Atropine, Tropane and Scopolamine. BH has pharmacological effects like bronchodilating, antisecretory, urinary bladder relaxant, spasmolytic, hypnotic, hallucinogenic, pupil dilating, sedative and anti-diarrheal properties. Clinical manifestations of acute BH poisoning are very wide which include mydriasis, tachycardia, arrhythmia, agitation, convulsion and coma, dry mouth, thirst, slurred speech, difficulty speaking, dysphagia, warm flushed skin, pyrexia, nausea, vomiting, headache, blurred vision and photophobia, urinary retention, distension of the bladder, drowsiness, hyper reflexia, auditory, visual or tactile hallucinations, confusion, disorientation, delirium, aggressiveness, and combative behavior. The main treatment of BH intoxicated patients is supportive therapies including gastric emptying (not by Ipecac), administration of activated charcoal and benzodiazepines. Health care providers and physicians particularly emergency physicians and clinical toxicologists should know the nature, medical uses, clinical features, diagnosis and management of BH poisoning.