In the recent past years, although the use of herbal plant products and supplements has increased to a large extent, overall only less than 80% of people rely on them to provide some basic healthcare services. Despite the fact that treatments including these agents have shown promising potential with their efficacy, many of them remain experimental and their use is poorly monitored. As a result, this often led to inadequate information about their mechanism of action and lead to potential adverse reactions, contraindications and interactions with existing pharmaceutical drugs and functional foods. The use of herbal plant medicine and dietary supplements can be risky as they are not subject to review by the Federal Drug Administration. Therefore, safety of herbal plants continues to be a major issue with the use of herbal remedies, where it becomes necessary. Owing to the lack of information about medicinal plants, may results in mistaking plants that contain toxins. This review discusses toxicity-related issues and major adverse effects arising from the use of herbal medicinal products and also highlights some important challenges related to the misidentification of herbal plants.