Gramicidin A is primarily used as an antibiotic to treat bacterial infections, especially those caused by Gram-positive bacteria. It is effective in disrupting bacterial cell membranes, leading to cell death. This makes it valuable in topical applications, such as ointments and creams, for treating skin infections and wounds. Additionally, it is used in research to study ion transport across membranes due to its ability to form channels that allow the passage of monovalent cations. In combination with other antibiotics, it enhances their effectiveness against resistant bacterial strains. Its role in membrane studies also contributes to understanding cellular processes and developing new therapeutic strategies.