Is Augmentin (amoxicillin/clavulanate) effective against Streptococcus pneumoniae and Haemophilus influenzae?

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From the FDA Drug Label

Amoxicillin for oral suspension is indicated in the treatment of infections due to susceptible (ONLY β-lactamase–negative) isolates of Streptococcusspecies. (α-and β-hemolytic isolates only), Streptococcus pneumoniae, Staphylococcusspp., or Haemophilus influenzae. Infections of the Lower Respiratory Tract:Amoxicillin for oral suspension is indicated in the treatment of infections due to susceptible (ONLY β-lactamase–negative) isolates of Streptococcusspp. (α-and β-hemolytic isolates only), S. pneumoniae, Staphylococcusspp., or H. influenzae.

Augmentin (amoxicillin/clavulanate) is effective against:

  • Streptococcus pneumoniae
  • Haemophilus influenzae However, it is only effective against β-lactamase–negative isolates of these bacteria. 1

From the Research

Augmentin (amoxicillin/clavulanate) is effective against both Streptococcus pneumoniae and Haemophilus influenzae, as it contains amoxicillin, which targets bacterial cell wall synthesis, plus clavulanic acid, which inhibits beta-lactamase enzymes that some bacteria produce to resist amoxicillin. This combination antibiotic works well against these common respiratory pathogens because Haemophilus influenzae frequently produces beta-lactamases, making the clavulanic acid component particularly important for effectiveness against this organism.

Key Points

  • For typical respiratory infections caused by these bacteria, Augmentin is commonly prescribed as 875/125 mg twice daily or 500/125 mg three times daily for adults for 7-10 days, with pediatric dosing based on weight 2.
  • Taking Augmentin with food helps reduce gastrointestinal side effects.
  • Patients should complete the full course of antibiotics even if symptoms improve before finishing the prescription.
  • Common side effects include diarrhea, nausea, and rash.
  • Patients with a history of penicillin allergy should not take Augmentin and should inform their healthcare provider about any allergies before starting treatment.

Evidence

Studies have shown that amoxicillin/clavulanate is effective against Streptococcus pneumoniae and Haemophilus influenzae, with a high bacteriological and clinical efficacy in respiratory tract infections 2, 3. The combination of amoxicillin and clavulanic acid provides a broad-spectrum of antibacterial activity, coverage of beta-lactamase-producing pathogens, and a favorable pharmacokinetic/pharmacodynamic profile 2.

Considerations

It is essential to consider the potential for resistance when prescribing antibiotics, and Augmentin should be used judiciously to maintain its effectiveness against these pathogens 3. Additionally, the emergence of drug-resistant strains, such as penicillin-resistant Streptococcus pneumoniae, should be taken into account when selecting an antibiotic regimen 4.

Dosage and Administration

The dosage and administration of Augmentin may vary depending on the specific infection being treated and the patient's age and weight. It is crucial to follow the recommended dosage and administration guidelines to ensure effective treatment and minimize the risk of side effects 2, 5.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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