Necrotizing Fasciitis Medication

Updated: Oct 12, 2022
  • Author: Steven A Schulz, MD; Chief Editor: Michael Stuart Bronze, MD  more...
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Medication Summary

Antibiotic therapy is a key consideration. Possible regimens include a combination of penicillin G and an aminoglycoside (if renal function permits), as well as clindamycin (to cover streptococci, staphylococci, gram-negative bacilli, and anaerobes).



Class Summary

Therapy must cover all likely pathogens in the context of the clinical setting.

Penicillin G (Pfizerpen)

Penicillin G interferes with synthesis of cell wall mucopeptide during active multiplication, resulting in bactericidal activity against susceptible microorganisms.

Clindamycin (Cleocin)

Clindamycin is a lincosamide for treatment of serious skin and soft tissue staphylococcal infections. It is also effective against aerobic and anaerobic streptococci (except enterococci). This agent inhibits bacterial growth, possibly by blocking dissociation of peptidyl transfer RNA (t-RNA) from ribosomes causing RNA-dependent protein synthesis to arrest. It is used as an alternative to penicillin G.

Metronidazole (Flagyl)

Metronidazole is an imidazole ring–based antibiotic active against various anaerobic bacteria and protozoa. It is used in combination with other antimicrobial agents (except for Clostridium difficile enterocolitis).

Metronidazole appears to be absorbed into cells of microorganisms containing nitroreductase. Unstable intermediate compounds that bind DNA and inhibit synthesis are formed, causing cell death.

Ceftriaxone (Rocephin)

Ceftriaxone is the drug of choice in initial treatment. It is a third-generation cephalosporin with broad-spectrum, gram-negative activity. It has lower efficacy against gram-positive organisms and higher efficacy against resistant organisms. It arrests bacterial growth by binding to one or more penicillin-binding proteins.


Gentamicin is an aminoglycoside antibiotic for gram-negative coverage. It is used in combination with both an agent against gram-positive organisms and one that covers anaerobes. It is not the drug of choice, but should be considered if penicillins or other less toxic drugs are contraindicated, when clinically indicated, and in mixed infections caused by susceptible staphylococci and gram-negative organisms.

Adjust the dose based on creatinine clearance (CrCl) and changes in volume of distribution. Follow each regimen by at least a trough level drawn on the third or fourth dose (0.5 h before dosing). Peak level may be drawn 0.5 h after a 30-min infusion.


Chloramphenicol binds to 50 S bacterial-ribosomal subunits and inhibits bacterial growth by inhibiting protein synthesis. It is effective against gram-negative and gram-positive bacteria.


Ampicillin has bactericidal activity against susceptible organisms. It is an alternative to amoxicillin when the patient is unable to take medication orally. It may be added to the initial regimen if the Gram stain suggests that enterococci are present.

Imipenem and cilastatin (Primaxin)

This combination is used for treatment of infections due to multiple organisms in which other agents do not have wide-spectrum coverage or are contraindicated because of potential for toxicity.

Ampicillin and sulbactam (Unasyn)

This combination of ampicillin and a beta-lactamase inhibitor covers skin, enteric flora, and anaerobes. It is not ideal for treatment of nosocomial pathogens.

Vancomycin (Vancocin)

Vancomycin is an antibiotic directed against gram-positive organisms and active against Enterococcus species. It is useful in the treatment of septicemia and skin-structure infections. Vancomycin is indicated for patients who cannot take or whose conditions fail to respond to penicillins and cephalosporins or those with infections with resistant staphylococci.

To prevent toxicity, the current recommendation is to assay vancomycin trough levels after the third dose, with samples obtained 0.5 h prior to the next dose. Use the CrCl to adjust the dose in patients with renal impairment.