Ceftazidime dihydrochloride is a third-generation cephalosporin antibiotic used to treat a wide range of severe bacterial infections, particularly those caused by Gram-negative bacteria, including Pseudomonas aeruginosa. It exerts its bactericidal effect by inhibiting the synthesis of the bacterial cell wall, binding to penicillin-binding proteins and disrupting peptidoglycan cross-linking, leading to cell lysis and death. Typically administered via intravenous or intramuscular injection, it is commonly prescribed for infections such as pneumonia, sepsis, urinary tract infections, respiratory tract infections, skin and soft tissue infections, and central nervous system infections like meningitis or encephalitis. It is especially useful in immunocompromised patients, including those with cystic fibrosis, cancer, or organ transplants, as well as for nosocomial infections, burn wounds, and post-surgical cases. Often employed in combination therapy with other antibiotics to broaden coverage against resistant or multi-drug Gram-negative pathogens.