Girls need urgent help, I'm starting to take Flumaximin Solutab for health…

Girls need urgent help, I'm starting to take Flumaximin Solutab for health reasons, the baby is on GVD, he's been there for 12 days. Please advise whether to continue breastfeeding and give probiotics BioGaia, or switch to formula after 5 days and supplement only at night so as not to get used to breastfeeding? I will take one tablet per day in the morning. Please share your experience. The consultant says that breast milk with antibiotics is better than formula. Thanks in advance.