Used to treat serious bacterial infections, particularly those caused by multidrug-resistant Gram-negative bacteria. Effective in treating infections of the respiratory tract, urinary tract, skin, bones, joints, and bloodstream. Often reserved for cases where other antibiotics have failed due to its potency and the risk of resistance development. Commonly used in hospital settings for immunocompromised patients or severe infections like sepsis and complicated intra-abdominal infections. Also used in combination therapy for tuberculosis when first-line drugs are ineffective.