From the Guidelines
Antibiotics are generally not recommended for treating gastroenteritis, as most cases are caused by viruses that don't respond to antibiotics. However, in specific cases where bacterial infection is confirmed or strongly suspected, antibiotics may be prescribed. For bacterial gastroenteritis caused by Campylobacter, azithromycin (500 mg daily for 3 days) or ciprofloxacin (500 mg twice daily for 3-5 days) may be used 1. For Salmonella infections, ciprofloxacin or trimethoprim-sulfamethoxazole might be prescribed in severe cases. Shigella infections may be treated with ciprofloxacin, azithromycin, or ceftriaxone. For Clostridium difficile, oral vancomycin (125 mg four times daily for 10-14 days) or fidaxomicin (200 mg twice daily for 10 days) is typically used 1. Some key points to consider when treating gastroenteritis include:
- The primary treatment for most gastroenteritis remains fluid replacement and symptom management while the infection runs its course.
- Antibiotics should only be used when necessary as they can disrupt gut flora and potentially worsen symptoms or lead to antibiotic resistance.
- The choice of antimicrobial agent may change due to evolving resistance patterns 1.
- In general, strive to use antibiotics covering a spectrum no broader than necessary and narrow the antibiotic spectrum of treatment after results of cultures and/or susceptibility tests become known 1. It's also important to note that some bacteria, such as STEC, should not be treated with antibiotics as it may worsen the condition 1. Overall, the treatment of gastroenteritis should be individualized based on the severity of the illness, the suspected or confirmed cause, and the patient's overall health status.
From the FDA Drug Label
Metronidazole tablets are indicated in the treatment of acute intestinal amebiasis (amebic dysentery) and amebic liver abscess. INTRA‑ABDOMINAL INFECTIONS, including peritonitis, intra‑abdominal abscess, and liver abscess, caused by Bacteroides species including the B. fragilis group (B. fragilis, B. distasonis, B. ovatus, B. thetaiotaomicron, B vulgatus), Clostridium species, Eubacterium species, Peptococcusniger, and Peptostreptococcus species.
Antibiotics for gastroenteritis may include metronidazole for specific cases, such as:
- Amebic dysentery
- Intra-abdominal infections, including those caused by susceptible anaerobic bacteria However, the use of metronidazole should be guided by culture and susceptibility information, and it should only be used to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria 2.
From the Research
Antibiotics for Gastroenteritis
The use of antibiotics in treating gastroenteritis depends on the causative agent and the severity of the symptoms.
- Most cases of gastroenteritis are caused by viruses, and therefore, do not require antibiotic treatment 3, 4.
- Bacterial causes that may warrant antibiotic treatment include Shigella, Vibrio cholerae, Campylobacter, and severe cases of Salmonella infection 3, 5, 4, 6.
- The choice of antibiotic depends on the suspected causative agent, host conditions, and local epidemiology 3, 4, 6.
Commonly Used Antibiotics
Some commonly used antibiotics for the treatment of gastroenteritis include:
- Azithromycin, which is preferred for infections due to Shigella and Campylobacter 3, 6, 7.
- Ceftriaxone and ciprofloxacin, which are recommended for salmonellosis when antibiotic treatment is indicated 3, 4, 6.
- Metronidazole, which may be used for empiric therapy in some cases 4, 6.
- Co-trimoxazole, which may be used as an alternative for empiric therapy 4.
Considerations for Antibiotic Use
- Antibiotic treatment should be avoided in most cases without bacteriological documentation 3, 4.
- Empiric therapy may be started while awaiting the results of microbiological investigations, especially in severe cases or when there is a high risk of spreading the infection 5, 4, 6.
- The emergence of antimicrobial resistance among gastroenteritis-causing pathogens is a concern, and antibiotic use should be guided by local epidemiology and susceptibility patterns 7.