I have a training partner that I told I was sick with strep throat and I was taking some antibiotics. He said dude your gonna mess up ur cyc. What exactly happens? Does something negative happen? I was kinda sick so I did have slightly less productive work outs. I took a strep antibiotic (az’forgot the rest) for 5 days. Any insight?
There is no problem, though of course being ill is somewhat of a problem.
The basis for what your friend said is that at least in the case of estrogens, enterohepatic recycling is a relevant phenomenon. What this means is that some estrogen is excreted in the bile as glucuronidated metabolites, which are inactive, but bacteria in the GI tract deglucuronidate them and they are reabsorbed. Thus, antibiotics decrease the effect of estrogen, as less of this reabsorption will occur.
So far as I know this process either does not occur or is not relevant with testosterone.
An abstract of an example article on the subject: http://ukpmc.ac.uk/articlerender.cgi?artid=968543