Diabetes mellitus represents a global health crisis affecting over 537 million adults worldwide, with projections indicating a rise to 783 million by 2045. Conventional antidiabetic therapies, while effective, are often associated with adverse effects, high costs, limited accessibility in resource-poor settings, and inadequate glycemic control in certain patient populations. Phytopharmaceuticals derived from medicinal plants offer promising complementary or alternative therapeutic options, supported by centuries of ethnopharmacological use and emerging scientific evidence. This article aims to critically review the current state of knowledge on phytopharmaceuticals for diabetes management, examining antidiabetic phytochemicals, their mechanisms of action, preclinical and clinical evidence, formulation strategies, safety profiles, and pharmacokinetic properties. Key phytochemicals including polyphenols, alkaloids, terpenoids, and flavonoids demonstrate multifaceted mechanisms such as enhancement of insulin secretion, improvement of insulin sensitivity, inhibition of carbohydrate-digesting enzymes, modulation of glucose transporters, and reduction of oxidative stress. Preclinical studies in cellular and animal models have demonstrated significant antidiabetic effects, while clinical trials have shown variable but encouraging results in glycemic control and metabolic parameters. Challenges related to standardization, bioavailability, formulation optimization, and potential herb-drug interactions require systematic attention. Regulatory frameworks for phytopharmaceuticals remain heterogeneous across jurisdictions. Future directions include development of standardized extracts with defined phytochemical compositions, rational combination therapies integrating conventional and plant-based medicines, advanced delivery systems to enhance bioavailability, and rigorous clinical trials to establish efficacy and safety. Integration of evidence-based phytopharmaceuticals into modern diabetes management protocols holds substantial promise for improving patient outcomes globally.