Cascabela thevetia (L.) Lippold. is an ornamental plant with traditional medicinal uses to treat oedema, diuretic, and cardiac disorders. The current review investigate the methods involved in the extraction and characterisation of phytochemicals from different parts of C. thevetia. In addition, the pharmacological potential, safety and toxicity of isolated pure phytochemicals from this plant were discussed in detail. The current review lists out a total of 81 phytochemicals that belong to terpenes, phenolics and flavonoids. The pharmacological potential of cardiac glycosides and flavonoids isolated from C. thevetia exhibited potent cytotoxic, antiviral and insecticidal activities under in vitro conditions. However, other pharmacological potentials and toxic effects of the isolated phytochemicals are not thoroughly investigated.