Penicillin is one of the most widely utilized broad-spectrum antibiotics worldwide, with a variety of clinical applications. It is effective against infections caused by gram-positive cocci, gram-positive rods, most anaerobes, and gram-negative cocci, making it a fundamental component in the treatment and management of various infections within the β-lactam antibiotic category. Most bacteria possess a peptidoglycan cell wall that surrounds the plasma membrane, providing protection against osmotic lysis and contributing to structural integrity. This peptidoglycan wall is continuously remodeled during bacterial growth and replication. Penicillin works by inhibiting the cross-linking of peptidoglycan in the cell wall.