Husband has stomach ache in middle of night and on the way to the bathroom passes out. More than a couple of instance of this. Worried. See doc?

Yes See Dr. This is not normal. Have him checked.
Go to ER. This is very serious. If he passed out tonight he needs to go to the ER. If not tonight he needs to get seen tomorrow somewhere, hopefully with his primary care doc. Gas pains can press on the vagal nerve and cause the heart rate to go so low that fainting occurs. But worse things can happen. Other causes of fainting could be from internal bleeding. Get seen! No splenda or sorbitol or imodium (loperamide).