I have stomach problems too. I have constipation and gas that I cannot control sometimes. Also, I have experienced bloating. I have not had frequent constipation prior to taking Levoxyl. I am not sure if it is due to Levoxyl. Hope this helps.
I just took .025 mg of Levoxyl for 10 days. It was a nightmare. Rapid pulse, extreme anxiety (and really tight back muscles to go with that), the hot feeling on the inside of your skin, HUGE amounts of bile and acid. Even with prilosec and maalox I could still feel burning in my stomach. Colon, abdominal pain. Needless to say, sleeping wasn't really in the cards. Unable to focus or function on much of any level. As it leaves my system, some cramping and diarrhea. At this point, I consider that the good news!
I just took .025 my Levoxyl for 10 days. It was a nightmare. Extreme anxiety (and tight back muscles and lack of sleep as a result), rapid pulse, hot - as others have described...like the inside of your skin is hot, MASSIVE amounts of bile and acid. Even with Prilosec and Maalox, I could feel the burning in my stomach. Colon and abdominal pain. I could not function on much of any level. I consider the cramping and diarrhea the good news that it's slowly leaving my system. But since the 1/2 life of this drug is 6-7 days, looks like abit longer til I'm OK again.