What are the oral antibiotics of choice for common bacterial infections?

From the Guidelines

The first-line oral antibiotics for common bacterial infections vary by infection type, with amoxicillin, azithromycin, and cephalexin being commonly used for respiratory and skin infections, while nitrofurantoin and trimethoprim-sulfamethoxazole are preferred for urinary tract infections. When considering the treatment of skin and soft tissue infections, the choice of antibiotic should be guided by the severity of the infection, the suspected causative organisms, and local resistance patterns 1. For example, for uncomplicated skin infections, cephalexin (500 mg four times daily for 7-10 days) or clindamycin (300-450 mg four times daily for 7-10 days) may be used, with clindamycin being preferred if MRSA is suspected 1. In the case of animal or human bites, amoxicillin-clavulanate (875/125 mg twice daily) may be used, although the choice of antibiotic should be guided by the severity of the bite and the suspected causative organisms 1. It's also important to consider the patient's allergies, pregnancy status, and renal function when selecting an antibiotic, and to complete the full course of treatment to prevent resistance development, even if symptoms improve earlier 1. Some key points to consider when choosing an oral antibiotic include:

• The type and severity of the infection
• The suspected causative organisms
• Local resistance patterns
• Patient allergies and medical history
• Pregnancy status and renal function
• The need to complete the full course of treatment to prevent resistance development. In general, the choice of oral antibiotic should be guided by the most recent and highest quality evidence, with consideration of the individual patient's needs and circumstances 1.

From the Research

Oral Antibiotics of Choice

The choice of oral antibiotics depends on the type of bacterial infection being treated. Some common oral antibiotics used to treat bacterial infections include:

• Amoxicillin/clavulanate, which is effective against a wide range of bacteria, including Streptococcus pneumoniae, Staphylococcus aureus, and Haemophilus influenzae 2
• Cephalosporins, such as cefdinir, cefpodoxime, and cefuroxime, which are effective against bacterial infections including community-acquired respiratory tract infections and other mild-to-moderate infections 2
• Amoxicillin, which is often used to treat bacterial infections such as sinusitis, pneumonia, and cystitis/pyelonephritis 3

Specific Infections and Antibiotic Choices

For specific infections, the following oral antibiotics may be chosen:

• Amoxicillin/clavulanate for bacterial sinusitis, community-acquired pneumonia, and uncomplicated cellulitis 4
• Cefdinir, cefpodoxime, or cefuroxime for community-acquired respiratory tract infections and other mild-to-moderate infections 2
• Amoxicillin for female cystitis/pyelonephritis and intra-abdominal infection with adequate source control and perioperative prophylaxis 4, 3

Considerations for Antibiotic Choice

When choosing an oral antibiotic, considerations include:

• The type of bacterial infection being treated
• The severity of the infection
• The patient's medical history and risk factors
• The potential for antibiotic resistance
• The need for antimicrobial stewardship to preserve the effectiveness of antibiotics 4, 5