[Serious plant poisonings in Switzerland 1966-1994. Case analysis from the Swiss Toxicology Information Center]

To analyze the types, frequency and severity of plant poisonings in Switzerland over 29 years.

Retrospective analysis of severe poisonings with toxic plants reported to the Swiss Toxicological Information Center (STIC). Assessment of the causality, severity of symptoms and the types of plants involved.

During the period under review the STIC registered 24 950 cases of contact with or ingestion of toxic plant material. In 99.4% of all cases the clinical course was either unknown, asymptomatic or associated with only minor symptoms (no hospitalization). Severe plant poisonings occurred in 152 cases. Detailed analysis was possible in 135 cases (23 children, 112 adults) including 5 lethal cases (all adults). The 24 plants involved produced the following severe symptoms: Atropa belladonna (42 cases): anticholinergic syndrome (42), acute psychosis (33), convulsions (2), coma (2). Heracleum mantegazzianum (18): severe photodermatitis (18). Datura stramonium (17): anticholinergic syndrome (17), psychosis (12), coma (2). Dieffenbachia (11): severe stomatitis (8), corneal lesions (3). Colchicum autumnala (10): diarrhea (10), liver necrosis (9), fatal multiorgan failure (2). Veratrum album (8): bradycardia ( < or = 40/min) (6), shock (5). Aconitum napellus (4): tachyarrhythmia (2), AV-block II/III (2). Aesculus hippocastanum (3): allergy (3), anaphylactic shock (2). Hyoscyamus niger (3): anticholinergic syndrome (3). Ricinus communis (3): diarrhea (3), toxic megacolon (1). Oenanthe crocata (2): convulsions (1), lethal coma (1). Taxus baccata (2): tachyarrhythmia (1), fatal asystole (1). Further single cases with severe poisonings were observed with Arum maculatum, Asarum europaeum, Chrysanthemum vulgare, Cyclamen persicum, Datura suaveolens, Glycyrrhiza glabra, Laburnum anagyroides, Lycopodium, Narcissus pseudonarcissus (lethal aspiration), Nerium oleander, Senecio vulgaris and Vicia faba.

Potential and real intoxications with plant materials occurred in 7.2% of all cases registered at the STIC. However, among all plant cases only 0.6% were severe intoxications requiring hospitalization. Although severe plant intoxications are rare events, a small number of specific plants appear to be mainly responsible for continued serious plant poisoning in Switzerland. The present study has identified the plants with the highest toxicological risks and provides a data base for more rational prevention, diagnosis and treatment of plant poisoning cases in the future.