For invasive disease, ampicillin plus an aminoglycoside is recommended. For penicillin-allergic patients, TMP-SMZ or high-dose vancomycin can be used. Cephalosporins are generally inactive. In the majority of patients with febrile gastroenteritis, the illness is self-limited (typical duration, 2 days or less) and therefore, generally no antibiotic treatment is necessary.
In pregnant women, listerial febrile gastroenteritis can lead to fetal death, premature birth, or infected newborns. Oral ampicillin or TMP-SMZ can be given for several days in immunocompromised or pregnant patients with listerial febrile gastroenteritis, particularly if they are still symptomatic once the culture result is known.