Hello, Thank you for using HCM Taxim is and Antibiotic that is used in different infections. The only case it is helpful in diarrhea is if your doctor has suspected typhoid fever. In this case the antibiotic might help with the diarrhea and also will be reducing the possibility to pass infection to others. Sometimes pneumonia (lung infection) can cause diarrhea and if the doctor heard the lungs and found pneumonia the antibiotics would be given also but as you prescribe fever and cough started late so this seems a less likely possibility. Hope this answers to your question and is helpful. Please feel free to write again if any questions