Is Amoxicillin (Co-amox) effective for treating an abscess?

From the Guidelines

Amoxicillin (Co-amox) is not the first-line treatment for abscesses, and its effectiveness is limited to specific cases where the primary treatment, incision and drainage (I&D), is not sufficient or is combined with antibiotic therapy for complicated abscesses. The primary treatment for most abscesses is incision and drainage (I&D), with antibiotics serving as an adjunctive therapy in certain cases, such as severe or extensive disease, rapid progression, signs and symptoms of systemic illness, associated comorbidities or immunosuppression, extremes of age, abscess in an area difficult to drain, associated septic phlebitis, or lack of response to I&D alone 1.

• For simple abscesses or boils, incision and drainage alone is likely adequate, and additional data are needed to further define the role of antibiotics, if any, in this setting 1.
• Antibiotic therapy is recommended for abscesses associated with specific conditions, such as severe or extensive disease, rapid progression, signs and symptoms of systemic illness, associated comorbidities or immunosuppression, extremes of age, abscess in an area difficult to drain, associated septic phlebitis, or lack of response to I&D alone 1.
• Amoxicillin-clavulanate (Co-amox) may be considered as an adjunctive therapy in cases where antibiotic treatment is necessary, particularly for providing coverage against many skin flora, including Staphylococcus aureus (though not MRSA), streptococci, and anaerobes 1.
• However, the most recent guidelines from 2018 recommend that impetigo, erysipelas, and cellulitis should be managed by antibiotics against Gram-positive bacteria, and empiric therapy for community-acquired MRSA (CA-MRSA) should be recommended for patients at risk for CA-MRSA or who do not respond to first-line therapy 1.
• The use of amoxicillin-clavulanate (Co-amox) should be guided by the severity and location of the abscess, as well as the presence of any underlying conditions that may affect the treatment outcome, and its effectiveness should be monitored closely, with immediate medical reevaluation necessary if the abscess does not improve within 48-72 hours of treatment or if there are signs of spreading infection.

From the Research

Effectiveness of Amoxicillin for Treating Abscesses

• Amoxicillin-clavulanate has been shown to be effective in treating certain types of abscesses, such as breast abscesses caused by Finegoldia magna 2.
• The efficacy of antibiotics, including amoxicillin, in treating abscesses can be influenced by factors such as the size and location of the abscess, as well as the presence of bacterial enzymes that can degrade the antibiotic 3.
• In some cases, amoxicillin-clavulanate has been used successfully to treat abscesses caused by Actinomyces, a type of bacteria that can cause severe wound infections 4.
• However, the use of systemic antibiotics, including amoxicillin, after incision and drainage of simple abscesses has not been shown to significantly improve cure rates 5.
• The choice of antibiotic and dosing regimen can be critical in determining the effectiveness of treatment, and antibiotics should be selected based on their ability to penetrate the abscess and reach effective concentrations 3.

Specific Cases and Studies

• A study published in 2017 reported the successful treatment of a breast abscess caused by Finegoldia magna with amoxicillin-clavulanate 2.
• A case report published in 2023 described the successful use of amoxicillin-clavulanate to treat a severe wound infection with wound communication secondary to Actinomyces 4.
• A meta-analysis published in 2014 found that systemic antibiotics, including amoxicillin, did not significantly improve cure rates for simple abscesses after incision and drainage 5.