Metformin is a plant-based drug belonging to the class of biguanides and is known to treat type-2 diabetes mellitus (T2DM). The drug, combined with controlling blood glucose levels, improves the body's response to insulin. In addition, trials have identified the cardioprotective potential of metformin in the diabetic population receiving the drug. Activation of 5' AMP-activated protein kinase (AMPK) is the major pathway for these potential beneficial effects of metformin. Historically, much emphasis has been placed on the potential indications of metformin beyond its anti-diabetic use. This review aims to appraise other potential uses of metformin primarily mediated by the activation of AMPK. We also discuss various mechanisms, other than AMPK activation, by which metformin could produce beneficial effects for different conditions. Databases including PubMed/MEDLINE and Embase were searched for literature relevant to the review's objective. Reports from both research and review articles were considered. We found that metformin has diverse effects on the human body systems. It has been shown to exert anti-inflammatory, antioxidant, cardioprotective, metabolic, neuroprotective, anti-cancer, and antimicrobial effects and has now even been identified as effective against SARS-CoV-2. Above all, the AMPK pathway has been recognized as responsible for metformin's efficiency and effectiveness. Owing to its extensive potential, it has the capability to become a part of treatment regimens for diseases apart from T2DM.

Andalusian Research Institute in Data Science and Computational Intelligence University of Granada Granada Spain

Chitkara College of Pharmacy Chitkara University Punjab India

Department of Chemistry Faculty of Science University of Hradec Králové Hradec Králové Czechia

Department of Neurology Charles University Prague Faculty of Medicine in Hradec Králové and University Hospital Hradec Králové Czechia

Department of Pharmacology Government Medical College and Hospital Chandigarh India

Department of Pharmacy BGC Trust University Bangladesh Chittagong Bangladesh

Department of Pharmacy Faculty of Allied Health Sciences Daffodil International University Dhaka Bangladesh

Department of Rasa Shastra and Bhaishajya Kalpana Faculty of Ayurveda Institute of Medical Sciences Banaras Hindu University Varanasi Uttar Pradesh India

Government Medical College Patiala Punjab India

Neurology Clinic University Hospital Hradec Králové Czechia

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