Antibiotics will be prescribed by MDLIVE physicians in accordance with good medical practice. As a result, when prescriptions are given, they will stick to the specified dose. There is no way of asking for additional antibiotics or changes to the prescription provided. In general, antibiotics kill both viruses and bacteria, so they're very useful if you have a virus that doesn't go away. They can also help if you have a bacterial infection. Antibiotics won't make any difference if you have a viral infection from a virus such as the common cold. That's because viruses are not affected by drugs either positively or negatively. However, antibiotics can help if you have a bacterial infection due to something like diarrhea. The diarrhea might be caused by the virus itself or by another bacteria along with the virus. Using antibiotics unnecessarily is a bad idea because it allows bacteria to build up a resistance to them. This means that in the future these same bacteria may not respond to antibiotics when you need them. If you get sick with a fever and cough and don't know whether it's a virus or a bacteria, a doctor can tell you whether antibiotics are needed. If you start taking antibiotics without talking to your doctor first, they could do more harm than good.