amphotericin B + cefotaxime + polymyxin E + tobramycin

This is a combination of four antimicrobial agents—amphotericin B, cefotaxime, polymyxin E (colistin), and tobramycin. Each component has a distinct mechanism of action:

• Amphotericin B is a polyene antifungal that binds to ergosterol in fungal cell membranes, creating pores that lead to cell death.
• Cefotaxime is a third-generation cephalosporin antibiotic that inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins.
• Polymyxin E (colistin) is a cationic polypeptide antibiotic targeting Gram-negative bacteria by disrupting the bacterial outer membrane through interaction with lipopolysaccharides and phospholipids.
• Tobramycin is an aminoglycoside antibiotic that binds irreversibly to the 30S subunit of bacterial ribosomes, inhibiting protein synthesis.

This combination may be used for selective decontamination in critically ill patients or for managing severe infections involving multidrug-resistant organisms. The rationale behind such combinations includes broad-spectrum coverage against both fungal and resistant Gram-negative pathogens.