Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concerns.. As per your complain the doses of antibiotics given to you are appropriate to treat sinus infection and you should continue with the same.. As far as having side effect of antibiotics as loose motions is concerned, it happens because the antibiotics disrupts the good bacteria present in intestines along with harmful bacteria and it leads to disturbances in the complex functioning of intestines like Digestion and Absorption and it leads to diarrhea.. It is however temporary and resolves as the antibiotic intake is stopped.. In case if you are fearful about having antibiotic induced diarrhea you can take certain preventive measure till you are on antibiotics to prevent digestive side effects.. As of now, till you are on medication you should take empty stomach Pantoprazole or Omeprazole.. Drink plenty of water.. Take more of yoghurt in diet as it is a probiotic and will help in maintaining bacterial flora of intestines.. You can also take probiotic pills by consulting your physician.. Hope this information helps.. Thanks and regards. Dr.Honey Nandwani Arora.