Antibiotic Drugs

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Daptomycin is a novel antibiotic first in the class of drugs known as lipopeptide.


Daptomycin is poorly absorbed orally and should only be administered intravenously. Intramuscular injection is prohibited as it causes direct toxicity.

Antimicrobial spectrum

Daptomycin is a bactericidal antibiotic selectively active against aerobic, facultative, and anaerobic gram-positive bacteria Gram-positive aerobes. Daptomycin is inherently inactive against gram-negative bacteria as they possess an outer membrane that the drug is incapable to penetrate and they lack specific factors essential for its activity. For more information on Daptomycin, click here.


Ertapenem sodium is a synthetic, parenteral carbapenem antibiotic.

Mechanism of action

The mechanism of action of ertapenem is similar to beta- lactam antibiotics. The bactericidal action of ertapenem is due to the inhibition of cell wall synthesis leading to death of bacteria.


After intramuscular administration peak plasma concentrations are reached in approximately 2 hours. For more information on Ertapenem, click here.


Fidaxomicin is a macrocycle antibiotic and is classified as a macrolide. It is derived from the fermentation products of Actinoplanes deccanensis and Dactylosporangium aurantiacum subspecies hamdenensis.

Mechanism of action

Fidaxomicin is thought to inhibit bacterial protein synthesis through non-competitive inhibition of transcription by binding to bacterial RNA polymerase. Fidaxomicin binds to σ subunits and due to this distinctive target site it has limited scale of antimicrobial activity and so has not reported cross-resistance with other antibiotic classes. For more information on Fidaxomicin, click here.

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