Please do not give your baby the Norfloxacin and Metronidazole combination. Norfloxacin is in the same antibiotic class as Ofloxacin; switching to it will not help if the previous treatment failed and can be harmful. Since the loose motions have lasted for 6 to 7 days, your baby needs an immediate pediatric evaluation to find the exact cause, which may be viral or require different management. Right now, focus on preventing dehydration. Give her Oral Rehydration Salts (ORS) solution frequently in small sips, and continue breast or formula feeding. See a doctor immediately if she has blood in her stool, high fever, or severe lethargy.