Antimicrobial peptides (AMPs) are crucial components of the innate immune defenses in all living organisms. These cationic peptides are produced constitutively or in response to bacterial products and exhibit broad-spectrum activity against bacteria, fungi, parasites, and viruses. They kill bacteria rapidly, are not easily resistant to, and synergize with conventional antibiotics and other peptides. AMPs also prevent cytokine induction by bacterial products and block sepsis in animal models. They are induced by lipopolysaccharide (LPS) and help regulate cytokine responses, suggesting a role in feedback regulation. AMPs are found in various species, including plants, insects, and mammals, and are involved in innate immunity. They are present in mucous layers and in neutrophils, where they contribute to nonoxidative killing. AMPs can be induced by bacterial products and are effective in protecting against infections. They are also involved in the regulation of gene expression in macrophages, reducing the expression of genes associated with inflammation. AMPs can inhibit LPS binding to LBP, preventing sepsis. They are also effective in animal models and have shown potential as therapeutic agents against antibiotic-resistant infections. AMPs can act synergistically with lysozyme and other peptides, enhancing their antibacterial activity. Despite their potential, challenges remain in their development as therapeutics due to their high molecular weight and potential toxicity. However, they show promise in clinical trials for treating infections and sepsis. AMPs are important in innate immunity and have potential as a new class of antibiotics.Antimicrobial peptides (AMPs) are crucial components of the innate immune defenses in all living organisms. These cationic peptides are produced constitutively or in response to bacterial products and exhibit broad-spectrum activity against bacteria, fungi, parasites, and viruses. They kill bacteria rapidly, are not easily resistant to, and synergize with conventional antibiotics and other peptides. AMPs also prevent cytokine induction by bacterial products and block sepsis in animal models. They are induced by lipopolysaccharide (LPS) and help regulate cytokine responses, suggesting a role in feedback regulation. AMPs are found in various species, including plants, insects, and mammals, and are involved in innate immunity. They are present in mucous layers and in neutrophils, where they contribute to nonoxidative killing. AMPs can be induced by bacterial products and are effective in protecting against infections. They are also involved in the regulation of gene expression in macrophages, reducing the expression of genes associated with inflammation. AMPs can inhibit LPS binding to LBP, preventing sepsis. They are also effective in animal models and have shown potential as therapeutic agents against antibiotic-resistant infections. AMPs can act synergistically with lysozyme and other peptides, enhancing their antibacterial activity. Despite their potential, challenges remain in their development as therapeutics due to their high molecular weight and potential toxicity. However, they show promise in clinical trials for treating infections and sepsis. AMPs are important in innate immunity and have potential as a new class of antibiotics.