Olizid-AV Solution for Infusion is a combination antibiotic formulation containing ceftazidime 2000 mg and avibactam 500 mg, indicated for the treatment of serious Gram-negative bacterial infections, including complicated intra-abdominal infections, complicated urinary tract infections, and hospital-acquired pneumonia. Ceftazidime, a third-generation cephalosporin, exerts bactericidal activity by inhibiting bacterial cell wall synthesis, while avibactam, a non-β-lactam β-lactamase inhibitor, enhances ceftazidime’s efficacy by inhibiting class A, C, and some class D β-lactamases, thereby overcoming resistance mechanisms. Olizid-AV is administered intravenously, ensuring rapid systemic distribution and optimal plasma concentrations critical for severe infections. The combination is particularly valuable against multidrug-resistant pathogens such as Pseudomonas aeruginosa and Enterobacteriaceae producing extended-spectrum β-lactamases (ESBLs) or carbapenemases. Dosage adjustments may be necessary in patients with renal impairment. Adverse effects are generally mild and may include gastrointestinal disturbances, hypersensitivity reactions, and transient liver enzyme elevations. Olizid-AV should be used under strict medical supervision, with therapy guided by susceptibility testing to optimize clinical outcomes and minimize resistance development. This solution for infusion represents a crucial option in the management of complicated infections caused by resistant Gram-negative bacteria.