The article provides an overview of metal-based nanoparticles as antimicrobial agents, focusing on their mechanisms of action, synthesis methods, physicochemical characterization, pharmacokinetics, and toxicological risks. Metal nanoparticles, particularly silver nanoparticles (AgNPs), are highlighted for their broad-spectrum antibacterial activity against both Gram-positive and Gram-negative bacteria. The review discusses the advantages of using metal nanoparticles, such as their non-specific bacterial toxicity and broad spectrum of activity, which makes them less likely to develop resistance. Various synthesis methods, including thermolysis, chemical reduction, biochemical, electrochemical, and wave-assisted chemical methods, are described, emphasizing the importance of size, shape, and surface charge in determining their effectiveness. The antimicrobial mechanisms of AgNPs are explained, including their attraction to bacterial surfaces, destabilization of cell walls, induction of oxidative stress, and modulation of signal transduction pathways. The pharmacokinetics of AgNPs, including absorption, distribution, metabolism, and excretion, are also discussed, highlighting the role of zeta potential and particle size in their behavior. Additionally, the article explores the broader range of biomedical properties of AgNPs, such as antifungal, antiviral, anti-cancer, and anti-inflammatory activities. Finally, the toxicity of AgNPs is assessed, considering their physicochemical properties and potential mechanisms of toxicity, including oxidative stress and genotoxic effects.The article provides an overview of metal-based nanoparticles as antimicrobial agents, focusing on their mechanisms of action, synthesis methods, physicochemical characterization, pharmacokinetics, and toxicological risks. Metal nanoparticles, particularly silver nanoparticles (AgNPs), are highlighted for their broad-spectrum antibacterial activity against both Gram-positive and Gram-negative bacteria. The review discusses the advantages of using metal nanoparticles, such as their non-specific bacterial toxicity and broad spectrum of activity, which makes them less likely to develop resistance. Various synthesis methods, including thermolysis, chemical reduction, biochemical, electrochemical, and wave-assisted chemical methods, are described, emphasizing the importance of size, shape, and surface charge in determining their effectiveness. The antimicrobial mechanisms of AgNPs are explained, including their attraction to bacterial surfaces, destabilization of cell walls, induction of oxidative stress, and modulation of signal transduction pathways. The pharmacokinetics of AgNPs, including absorption, distribution, metabolism, and excretion, are also discussed, highlighting the role of zeta potential and particle size in their behavior. Additionally, the article explores the broader range of biomedical properties of AgNPs, such as antifungal, antiviral, anti-cancer, and anti-inflammatory activities. Finally, the toxicity of AgNPs is assessed, considering their physicochemical properties and potential mechanisms of toxicity, including oxidative stress and genotoxic effects.