The Caribbean region comprises several small, tropical, mainly volcanic islands, which possess a rich diversity of flowering plants; hundreds of these plants are used to make traditional folk remedies for a variety of ailments. However, some of the natural constituents in these herbal folk remedies may be injurious to human health. The aim of this review is to raise awareness of the poisonous substances contained in several Caribbean medicinal plants, which may have significant consequences for public health. The databases of PubMed, the US FDA poisonous plants, and Natural Standard were searched for information relating to toxic plant constituents, the Caribbean Herbal Pharmacopoeia and public health issues arising from potentially harmful herbal remedies. Search terms included: Caribbean folk medicine, herbal medicine, herbal remedies, phytotherapy, poisonous plants, plant toxins and herbal pharmacotherapy. Authors also hand searched journal articles in toxicology and reports from several regulatory agencies concerning public health risks of herbal medicines. Seventeen plants that are currently used as Caribbean folk remedies were identified as potentially injurious species because they contain known toxins. Perhaps the most harmful of these plants is Lantana camara. It was also found that only limited knowledge was available to precisely direct the management of any specific plant poisoning. Sustained popularity of Caribbean folk medicine is likely to increase the frequency of cases of toxicity. More reporting is recommended from healthcare professionals concerning suspected cases of adverse reactions with herbal remedies.