Neurontin and urination

I started dating a guy that takes neurontin, thus the reason I am researching this drug. He is taking it for mood swings and a.d.d. He doesn't take it constitently. He takes various doses depending on the circumstances (sometimes he takes it like a party drug and he drinks). I can tell right away when he has taken a higher dose. He is lethargic, he drools, he is off balance, and actually seems somewhat slow (mildly retarded). I know he is intellegent, however, this drug is making him into a person that he should not want to be. I don't know if I can continue a relationship with someone that seems to be drugging himself to a complete stupor.
He said he was going to cut down to one pill, three times a day, however, I think he is having a very difficult time doing that. He is very addicted to his MEDS as he calls them. This drug seems to be destroying his life and he doesn't even know it.
He continually has to urinate, has a low sex drive and he experiences stomach problems along with back problems. This is the only drug that he takes. After what I have seen I wouldn't prescribe this to my worst enemy.

i have been taking neurontin for about 3 or 4 years now. i am also on several other meds. verapamil 120mg bid,cytomel 25mg 1/2 tab qd,valium 5 mg 1 tab tid,zoloft 100mg 2 tab qd, levoxyl 0.125mg qd and imertrex 100mg at start of migraine plus more later if needed(which i won't do) recently i have been having a burning tounge. my dr. says it could be one of my meds.'turning against me'. i also urinate all of the time. i can't go anywhere! i also can't urinate if i take almost any psytrophic drugs because i can't release it from my bladder. i have been schizo-affective for many years now. only within the last year have the meds.started to bother me. could the neurontin be the cause of my burning tounge and frequent urination? i already know which meds. that i use to be on that caused the inability to release urine from my bladder. i don't take those anymore? any help would be appreciated. my doctors are stumped. oh yes , my kidneys and bladder are ok i had them checked out by specialist. sorry. my neurontin is 300mg qd.