Salmonella infections usually resolve in three to seven days and, many times, require no treatment. Persons with severe diarrhea may require rehydration, often with intravenous fluids. Antimicrobial therapy (or treatment with antibiotics) is not recommended for uncomplicated gastroenteritis. However, antibiotics are recommended for persons at increased risk of invasive disease, including infants younger than three months of age.
In situations in which antibiotics are needed, trimethoprim/sulfamethoxazole, ampicillin, or amoxicillin are considered by many physicians to be the best choices. Ceftriaxone, cefotaxime, or fluoroquinolones are effective options for antimicrobial-resistant strains, although fluoroquinolones are not approved for persons less than 18 years of age. For persons with an infection in a specific organ or tissue (invasive disease), treatment with an expanded-spectrum cephalosporin is commonly employed. Ideally, the choice of antibiotic is driven by antimicrobial susceptibility testing on the specific bacterium isolated in the lab. Treatment with antibiotics may vary from two to four weeks, depending on the severity and length of infection. For enteric fever, including S. Typhi infections, treatment for 14 days is often advised.