Alan Scott, Facebook asked:
Do antibiotics kill good bacteria?
Karen - A lot of antibiotics prescribed are indiscriminate and they will kill our good bacteria as well as the targeted bacteria that they want to kill. They do destroy your gut bacteria and that's sometimes why, when you take a course of antibiotics, you get an upset stomach, diarrhoea et cetera. The best way to try and avoid that is to take some of these probiotic yogurts whilst you're taking the course of antibiotics and possibly for a week or so afterwards. Just to give your own bacteria a chance to recover because although a certain number of your own bacteria will get killed, and that can cause the upset stomach, there are still enough left there that they will regenerate once the antibiotic pressure is removed.
Chris - It’s often said that the spectrum of bugs that you have in your intestines is more unique to you than your own fingerprint is. So if antibiotics wipe out some of those bacteria, can you actually get back the very ones you had before or do you end up substituting some that are vaguely right, but they're not exactly what you had previously?
Karen - Generally, they do all come back because if you imagine the surface of the gut is like your fingers. There are deep crypts and everything is in there, so the bacteria find hiding places away from the antibiotics. So generally, most of them come back again. There are certain bacteria that seem to be particularly susceptible and can get lost. One of them for example is a species called oxalobacter and if you don't have oxalobacter, you're more likely to get kidney stones. Oxalobacter can be eliminated forever with certain antibiotics.