- Since the vast majority of plant exposures are unintentional and involve small quantities, most patients do not develop any symptoms.
- Gastrointestinal upset is the most common manifestation of symptomatic exposure.
- Dieffenbachia and Philodendron are houseplants and are common causes of symptomatic plant ingestions. They can cause oral and pharyngeal pain from injection of insoluble calcium oxalate crystals.
- During the Christmas holidays, children are often exposed to poinsettia, mistletoe, and holly.
- Foxglove, oleander, and lily of the valley are among several species of plants that contain cardiac glycosides and may cause toxicity similar to digoxin intoxication.
- Water hemlock is easily confused with the wild carrot. The potential for serious toxicity is significant and patients may progress to status epilepticus, rhabdomyolysis, respiratory distress, and death.
Evaluation of a patient with a plant exposure presents several challenges to the health care provider. Significant geographical variation in plant species exists. Historical information regarding the species of plant as well as the amount ingested is often lacking. The degree of toxicity expected may depend on the particular part of the plant structure ingested such as seeds, fruit, stem, or root. Plants vary in toxicity during different stages of their growth cycle. Mechanical preparation of the plant material may also affect the overall toxicity. Furthermore, there is considerable overlap in the clinical manifestations of toxicity of many plants. Although the majority of plants do not cause clinical toxicity, a small number are mildly toxic and a few are harmful with even a small exposure.
According to American Association of Poison Control Center (AAPCC) data, 64 236 human exposures to plants were reported in 2006, accounting for 2.7% of the catalogued human exposures. The clear majority of these exposures occurred in pediatric patients, with 44 710 plant exposures reported in children ≤5 years of age.1 The majority of plant ingestions are fairly benign events, with only a single fatality attributed to a plant or herbal/botanical product in the 2006 AAPCC National Poison Data System (NPDS) annual report.1 With regard to pediatric cases, two common scenarios exist. Nearly 70% of plant ingestions are by children younger than 6 years.1 Toddlers and other young children may ingest plant material while exploring their environment. Many of these ingestions involve small or insignificant amounts. In the second common scenario, older children and adolescents may intentionally consume specific plant species for their purported psychoactive effects. Despite the fact that the latter group of ingestions may carry a higher risk of morbidity, significant toxicity is relatively rare.
Plant name and/or accurate species information may not always be readily available to the clinician. Historical information to be elicited includes whether the plant is an indoor or outdoor variety and a description of the plant's flower, stem, leaves, height, and location. Consultation with a botanist, medical toxicologist, or poison control center is highly recommended whenever assistance is needed in identifying an unknown plant. Transmission of digital color or facsimile images ...