ceftriaxone + clarithromycin + metronidazole

This is a combination antibiotic regimen consisting of three agents:

• Ceftriaxone is a third-generation cephalosporin antibiotic with broad-spectrum activity against Gram-negative and some Gram-positive bacteria. It acts by inhibiting bacterial cell wall synthesis.
• Clarithromycin is a macrolide antibiotic that inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit, effective against various respiratory and atypical pathogens.
• Metronidazole is an antimicrobial agent primarily active against anaerobic bacteria and certain protozoa, working through DNA strand breakage after reduction in anaerobic cells.

This combination has been studied for the treatment and prevention of intra-amniotic inflammation/infection, particularly in patients with preterm premature rupture of membranes (preterm PROM). Clinical studies have shown that this regimen can more effectively eradicate intra-amniotic infection/inflammation compared to older regimens (such as ampicillin/cephalosporins), reduce secondary infections, and lower rates of funisitis—a marker for fetal inflammatory response syndrome. The drugs are administered as ceftriaxone injection plus oral clarithromycin and metronidazole.