The use of blooms of flowering plants for culinary and medicinal purposes around the globe dates back to ancient times and is known as edible flowers. The edible part of the flower may vary in each variety of bloom. The edible parts of the flowers, namely the pollen, nectar, and petals, are rich sources of essential nutrients and bioactive compounds, including carbohydrates, proteins, lipids, vitamins, minerals, and phytochemicals such as carotenoids, alkaloids, flavonoids, and phenolic compounds. These flowers are known for their beneficial pharmacological potential, including anti-microbial, anti-anxiety, anti-cancer, anti-inflammatory, antioxidant, hypoglycemic, diuretic, anthelmintic, and immunomodulatory properties. Despite their benefits, edible flowers can also pose risks such as asthma, hay fever, and allergies, leading to fatality due to pathogenic bacteria and chemical compounds from the environment and horticultural activities. Flowers can also contain lethal and anti-nutritional factors like cyanogenic glycosides, alkaloids, trypsin inhibitors, hemagglutinins, and oxalates. Poisonous flowers may contain dimethoate, sulfite, and pathogenic microorganisms like Salmonella spp. Therefore, there is a need to identify the toxic effects of edible flowers in food and medicine and the dose responsible for the toxicity to avoid serious adverse effects. Although there are no official food safety and security laws by any regulatory agencies for its use and marketing around the globe, identifying the toxic effects of these edible flowers as per OECD guidelines or WHO guidelines for herbal drugs would aid in utilizing edible flowers more confidently and enhance its market potential. This review will highlight the various adverse effects of edible flowers and the reason for their toxic effects. Furthermore, a note on the different protocols to identify the harmful effects for better acceptability of edible flowers as functional foods would be outlined.