Everytime I go to sleep to try going into a lucid dream (lying on my back), a little moment later I feel the urge to swallow because I suddenly get the feeling of something in my throat. I try to fight it, but for some reason I can’t, and I automatically swallow before I even know it. This ruins all my concentration and I have no chance of LDing anymore. I was able to have a good LD once, but that was before I started having these strange distracting urges. Is there any way to stop them? 
I also have this but more in my legs, it’s terrible! But I think you just have to let everything go automatic, don’t focus on your body but create a dream scene in your mind…
If you have to swallow, swallow! 
I don’t think the swallowing interfeirs much with your chances of having a LD, what interfeirs is how much attention you give it…
If you focus on not swallowing, well, that will break your concentration… So if you have to swallow, just swallow and don’t give it much attention. Then get back to what you were doing… 