Which one of the following is considered as the drug of last resort for human beings ?

Chloramphenicol is historically and clinically recognized as a 'drug of last resort' for specific life-threatening infections. While it is a potent broad-spectrum antibiotic that inhibits protein synthesis, its use is strictly limited due to severe potential side effects, such as bone marrow suppression and aplastic anemia. In contrast, Penicillin, Tetracycline, and Streptomycin are widely used first-line or common antibiotics, though their effectiveness has declined due to widespread resistance [1]. While modern medicine often cites Vancomycin or Colistin as contemporary last-resort drugs for multidrug-resistant 'superbugs' like MRSA, among the provided options, Chloramphenicol is the one traditionally reserved for critical cases where other safer alternatives fail or are contraindicated. It remains a vital treatment for conditions like bacterial meningitis or typhoid fever in specific clinical scenarios where resistance to other drugs is present.

Sources

1. [1] https://pmc.ncbi.nlm.nih.gov/articles/PMC8541462/