Hey
@joanneallison 
A belated welcome to the forums, coming your way in 3... 2... 1... WELCOME!
Starting just from a position of logic here, you would need to be more specific with your question. Are you asking if x-rays are applied to an inert substance
in vitro or "out of the body" or are we talking about
in vivo chemicals already in your body that are reacting to these x-rays?
From a more practical position, this question is pretty far beyond what we are capable of handling here. We're not neuroscientists, we're basically just drug addicts who coincidentally like learning about our drugs. This would be a question to pose to a physicist/physician/chemist or some combination of the 3.
We know that x-rays have a wide range of effects on organic matter. They are potentially dangerous, yes. In the world of modern medicine, which is where this fits in, x-ray usage is pretty much down to a precise science. We know how much people can tolerate before damage is done. Precautions are taken (lead aprons and such for instance), the time exposed to the radiation is kept to a minimum and getting an x-ray is essentially harmless.
It would be a pretty crazy revelation to find out you were being pumped with enough x-ray radiation to change the chemical processes of your body in a way that is subjectively noticeable to you. That being said, if you're concern is regarding having had an x-ray, I'm sure you're fine and no, there isn't any data to imply that drugs in your system are going to act differently following an x-ray.
If you're talking about exposing drugs to x-rays or sometehing like that, I'm really not sure. The better question would be why are you exposing drugs to x-rays in the first place. The answer to the latter would probably negate the need to answer the former.
Anyway, I'm happy to leave this open for a tick, just give us some more detail about what you're trying to figure out.
