Has your Gastrointerologist ever bothered to figure out WHAT WAS CAUSING your CONSTIPATION? Probably not. My father has Ulcerative Colitis & GERD, my mother has IBS & GERD, my brother has Barretts & I have GERD. We are all on different medication. Prilosec, Nexium, Protonix, and Prevacid. Yup, bad genes. And, my little 9 year old daughter was recently diagnosed with GERD after suffering from hearburn, stomach aches, reflux, SEVERE constipation, gas and indigestion for years. 
Pepcid & Zantac did nothing. Finally they put her on Prevacid 2 mos. ago. It helped a little, but not much...she still had stomach aches, gas, SEVERE constipation and still had reflux at night. The first GI Dr. added Sucralfate at night & the reflux finally subsided a bit. But, she was still constipated (went once every 4 days at the most - always little balls) and she still had severe stomach aches and TONS AND TONS OF GAS!! Also, Sucralfate causes constipation!! I FIRED her Doctor and found a new one!! After a (normal) ultrasound and blood work, he ordered a "modified lactose breath hydrogen test." It tests for lactose/sugar malabsorbtion or BACTERIAL OVERGROWTH OF THE UPPER INTESTINES or ANYWHERE ELSE in the digestive tract. I thought he was nuts 
because after reading about BACTERIAL OVERGROWTH, it made no sense. She was not thin, she did NOT EVER have diarrhea, nor did she suffer from malnutrition. WELL, HE WAS RIGHT!! SHE TESTED POSITIVE FOR BACTERIAL OVERGROWTH!!! Yippie!! Finally, a diagnosis AND a cure!! He put her on a high dose of Flagyl (a strong antibiotic) for 10 days to DESTROY ALL of the bacteria (even the good ones) in her entire digestive tract. Now she is taking VSL#3 to restore the right bacteria to the digestive tract. She's only been on the VSL#3 for 4 days and guess what? NO STOMACH ACHES, NO REFLUX, NORMAL BMs EVERY DAY (which she doesn't like...LOL) AND NO GAS, NO MORE CONSTIPATION!! 
She started to get better on her 6th day of the HIGH DOSE of Flagyl, and has been getting better and better. Thank God...I can sleep through the night again. Poor little darling. Well, needless to say, the Dr. thinks the BACTERIAL OVERGROWTH caused the reflux AND the stomach cramps/pain AND constipation can cause BACTERIAL OVERGROWTH! She even had pain in her esophagus. AND she said she could feel the food going down when she ate!! I'm not a Doctor, but I'd be willing to bet that you have NO digestive bacteria left in you esophagus, which is caused by BACTERIAL OVERGROWTH elsewhere in your digestive tract. Your problem is probably bacterial overgrowth in your stomach, which destroys the bacteria needed to digest your food in your esophogas. Also, do yourself a big favor and try Colace (a stool softener) every day, instead of a laxative. I've been taking it for years. I feel GREAT!! Also, it helped when I switched to Protonix (Prilosec was KILLING ME,) and I also switched to Klonopin from Xanax. Well eventually, my little girl may no longer even need the Prevacid in the AM or the Sucralfate at night. Oddly enough, my father said he had the exact same problems as a child, but they had no test back then. And, if BACTERIAL OVERGROWTH goes untreated, it almost always causes Ulcerative Colitis or Crohn's disease. So this is NOT a coincidence in my opinion. My Dad has Ulcerative Colitis. IMPORTANT! CONSTIPATION CAUSES BACTERIAL OVERGROWTH AND BACTERIAL OVERGROWTH CAUSES CONSTIPATION!! You should DEMAND THE TEST! All you have to do is drink some sugar & water stuff, then blow into a different bag every 15 minutes for about 4 hrs. They label the bags and if there is a hydrogen "spike" in one or more of the bags based on the "time" you blew into the bag, they can tell right where (in your intestinal tract) the problem is, if there is one. If there is too much bacteria in a certain area, it causes excessive amounts of hydrogen (gas) to actually go into the lungs from the digestive tract. And too much bacteria causes the gas. If it isn't expelled, it causes constipation, gas and/or pain. It's not an invasive test and it could be your answer. I will keep you posted as to how she is doing. P.S. If anyone has Ulcerative Colitis and reads this, let me know if you would like a list of "what to eat and what not to eat." My Dad has been in remission for over 55 years. His colitis has been under control due to "his" diet only. You'd be surprise what you can actually eat!! He has it down to a science. Good Luck. 
