Hi, Regarding her antibiotic treatment for MAC infection, it s important to follow the instructions provided by her healthcare provider or pharmacist. Typically, Azithromycin, Rifampin, and Ethambutol are taken together at once, as they work together to effectively treat the MAC infection. However, the dosing schedule may vary depending on the specific instructions given by the healthcare provider, as well as the severity of the infection and other factors. It s important to take the antibiotics as directed by the healthcare provider, and to take them at the same time each day. If a dose is missed, it should be taken as soon as possible, but if it s closer to the time for the next dose, the missed dose should be missed and continue with the regular dosage schedule. Taking the antibiotics at the same time each day helps to maintain a consistent level of the drug in the body and ensures the best possible outcome for treatment. If you or your mother have any questions or concerns about her medication regimen, it s always best to consult with her healthcare provider or pharmacist. They can provide specific guidance based on her individual needs and medical history. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Diwashish Biswas, Internal Medicine Specialist