Table 2.

Parenteral regimens for empiric treatment of pyelonephritis in pregnancy

Antibiotic	Dose, interval
Mild to moderate pyelonephritis
Ceftriaxone	1 g every 24 h
Cefepime	1 g every 12 h
Aztreonama	1 g every 8 h
Ampicillin	1–2 g every 6 h
PLUS
Gentamicinb	1.5 mg/kg every 8 h
Severe pyelonephritis with an impaired immune system and/or incomplete urinary drainage
Ticarcillin-clavulanate	3.1 g every 4 h
Piperacillin-tazobactam	3.375 g every 6 h
Meropenem	500 mg every 8 h
Ertapenem	1 g every 24 h
Doripenem	500 mg every 8 h

Doses are for patients with normal renal function. If methicillin-resistant S. aureus (MRSA) is known or suspected, see treatment regimens outlined separately in topics addressing MRSA management

^aAlternative in the setting of beta lactam allergy

^bAminoglycosides have been associated with fetal ototoxicity; this regimen should be used only if intolerance precludes the use of less toxic agents