Is vancomycin (Vanc) and ceftazidime (Ceftaz) a broad coverage antibiotic combination?

From the Guidelines

Yes, vancomycin (Vanc) and ceftazidime (Ceftaz) can be considered a broad coverage antibiotic combination in certain clinical contexts, such as hospital-acquired pneumonia or ventilator-associated pneumonia, where coverage against both gram-positive and gram-negative pathogens, including Pseudomonas aeruginosa and MRSA, is necessary. This combination provides coverage against a wide spectrum of pathogens, with vancomycin targeting gram-positive organisms including methicillin-resistant Staphylococcus aureus (MRSA), while ceftazidime is a third-generation cephalosporin with strong activity against gram-negative bacteria, including Pseudomonas aeruginosa, as noted in the guidelines for the management of hospital-acquired pneumonia and ventilator-associated pneumonia 1.

However, the use of this combination should be guided by local antibiograms and the specific clinical context, including the risk of multidrug-resistant (MDR) pathogens and the severity of the infection. In settings where the risk of MDR pathogens is high, such as in healthcare-associated infections, a broader spectrum of activity may be required, and the addition of other agents or the use of different antibiotics altogether may be necessary, as discussed in the management of intra-abdominal infections 1.

The dosing of vancomycin is typically weight-based (15-20 mg/kg every 8-12 hours) with therapeutic drug monitoring to maintain appropriate trough levels, while ceftazidime is usually dosed at 1-2 grams every 8 hours, with adjustments needed for renal impairment. It's also important to note that once culture results return, this broad coverage should be narrowed to more targeted therapy when possible to reduce the risk of antimicrobial resistance and adverse effects.

Some key points to consider when using vancomycin and ceftazidime include:

• The importance of therapeutic drug monitoring for vancomycin to ensure adequate trough levels and minimize the risk of nephrotoxicity.
• The need for dose adjustments of ceftazidime in patients with renal impairment to avoid accumulation and potential toxicity.
• The potential for ceftazidime to be ineffective against certain gram-negative pathogens, such as ESBL-producing Enterobacteriaceae, and the need for alternative or additional therapy in such cases.
• The importance of considering local resistance patterns and antibiograms when selecting empiric antibiotic therapy, as highlighted in the guidelines for the management of intra-abdominal infections 1.

Overall, while vancomycin and ceftazidime can provide broad coverage against a wide range of pathogens, their use should be tailored to the specific clinical context and guided by local resistance patterns and antibiograms, as well as the principles of antimicrobial stewardship to minimize the risk of resistance and adverse effects.

From the FDA Drug Label

Vancomycin solution exhibits a physical incompatibility when mixed with a number of drugs, including ceftazidime. The bactericidal action of vancomycin results primarily from inhibition of cell-wall biosynthesis. Vancomycin is not active in vitro against gram-negative bacilli, mycobacteria, or fungi Ceftazidime has been found compatible for 12 hours at room temperature or for 3 days under refrigeration in 0.9% Sodium Chloride Injection or 5% Dextrose Injection when admixed with: cefuroxime sodium, heparin, or potassium chloride

Vancomycin and Ceftazidime are two antibiotics with different mechanisms of action and spectrums of activity.

• Vancomycin is effective against gram-positive microorganisms, including methicillin-resistant Staphylococcus aureus (MRSA).
• Ceftazidime is a cephalosporin antibiotic with activity against gram-negative microorganisms, including Pseudomonas aeruginosa. The combination of Vancomycin and Ceftazidime may provide broad coverage against both gram-positive and gram-negative microorganisms. However, due to the physical incompatibility of Vancomycin and Ceftazidime, they should be administered separately, flushing the IV lines between the administration of these two agents 2.

From the Research

Antibiotic Coverage

• Vancomycin (Vanc) has a bactericidal effect on gram-positive cocci and bacteria, as well as some gram-negative cocci 3.
• Ceftazidime (Ceftaz) is effective against gram-negative bacteria, including Pseudomonas aeruginosa 4, 5.

Combination Therapy

• The combination of vancomycin and ceftazidime has been shown to be effective in treating various bacterial infections, including those caused by methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa 4, 5.
• This combination therapy can help prevent the replacement of opportunistic infections, as vancomycin is effective against gram-positive bacteria and ceftazidime is effective against gram-negative bacteria 4.
• The pharmacokinetics and serum bactericidal activity of vancomycin alone and in combination with ceftazidime have been investigated, and no antagonistic effects were observed 5.

Broad Coverage Antibiotics

• The combination of vancomycin and ceftazidime can be considered a broad coverage antibiotic combination, as it is effective against a wide range of gram-positive and gram-negative bacteria 4, 5.
• However, other antibiotics, such as S-3578, a new broad-spectrum cephalosporin, have also been shown to have potent in vitro and in vivo activity against gram-positive and gram-negative bacteria, including MRSA and Pseudomonas aeruginosa 6.