Patient description: The patient is a 41-year-old obese woman coming to the emergency room with abdominal pain and vomiting. The pain that started gradually yesterday is located in the epigastric and periumbilical regions, radiating to her back. She drinks alcohol frequently and does not smoke. She has no history of allergies and uses only multivitamins daily. Her family history is positive for hypertension (her mother). She lives with her husband and has 3 children. The abdomen is tender and soft. Her bowel sounds are normal. Her heart rate is 115/min and blood pressure 110/75 mmHg. The lab studies are remarkable for leukocytosis (19.5), urea of 8.5, high CRP (145), high amylase (1200) and Glucose level of 15. Her abdominal CT scan revealed acute edematous interstitial pancreatitis with enlarged common bile duct and intrahepatic duct confirming gall stone pancreatitis. Her pregnancy test is negative and she is not breastfeeding.

Clinical trial eligibility criteria: eligible ages (years): 18.0-75.0,  Constipation-predominant IBS (IBS-C) History 1. Between the ages of 18-75 2. Have recurrent abdominal pain or discomfort at least 3 days/month in the last 3 months 3. Have at least 2 of the following in the last 6 months: 1. Improvement of abdominal pain or discomfort with defecation 2. Onset of abdominal pain or discomfort associated with change in frequency of stool 3. Onset of abdominal pain or discomfort associated with a change in form/appearance of stool 4. Symptom onset at least 6 months prior to screening date 5. Willing to take study supplement three times a day and willing to comply with all study procedures (i.e. swallow capsules) 6. Willing to stop taking over-the-counter laxatives after the 2 week screening period (Ex: ex-lax, senna, miralax, milk of magnesia) Screening Diary 7. Abdominal bloating/discomfort/pain (if either a, b, OR c is positive, then this meets the for #7) 1. A weekly average of worst abdominal bloating score of ≥ 3 during the screening period on a 0-10 numeric rating scale 2. A weekly average of worst abdominal discomfort score of ≥ 3 during the screening period on a 0-10 numeric rating scale 3. A weekly average of worst abdominal pain score of ≥ 3 during the screening period on a 0-10 numeric rating scale 8. Bowel movements/stool consistency (if either a OR b is positive, then this meets the for #8) 1. Less than 3 spontaneous complete BM (SCBM) per week. (SCBM is defined as a BM occurring in the absence of a laxative that is associated with a sense of complete evacuation) 2. Stool consistency of 1-2 on Bristol scale at least twice a week OR >25% of BM for the week Lab Results 1. Abnormalities in CBC (Hgb<12 g/dL, platelet count<100000, WBC<4000 or >10000) 2. Abnormal liver function tests (ALT, AST, alkaline phosphatase, or bilirubin >1.5 times normal range) 3. Abnormal renal function tests (BUN or creatinine >1.5 times normal range) 4. Low serum albumin (<3 g/dL) 5. Uncontrolled thyroid disease as evident from abnormal TSH level 6. High CRP (> 5), except those evaluated for IBD and IBD is ruled out through colonoscopy, CT or additional tests 7. Insulin-requiring and/or poorly controlled diabetes (well-controlled diabetics with HbA1c <7 may be enrolled) History 8. Patient history of GI diseases (except for hemorrhoids or occasional (<3 times a week) heartburn) 1. Inflammatory bowel disease (Ex: ulcerative colitis, crohn's disease, any colitis) 2. Celiac disease 3. Colonic inertia (lazy/slow colon resulting in surgery, resection or daily laxatives) 4. Diverticular stricture (narrowing of the colon) 9. Antibiotic use within last 4 weeks 10. Severe uncontrolled hypertension 11. Significant uncompensated cardiac or respiratory diseases (defined as requiring daily medication for management of their diseases (Ex: on oxygen or can't walk)) 12. Prior extensive intestinal resection 13. History of psychiatric hospitalization OR suicide attempt in the last 5 years 14. Drug and/or alcohol abuse 15. Plan to have a major change of their dietary habit during the following 5 months 16. Drug induced constipation (Ex: opiates) 17. Pregnant or lactating 18. Use of narcotic medications (pain killers, Ex: hydrocodone, methadone, morphine, oxycodone or tramadol) or anticoagulant/antiplatelet agents (ex: heparin, warfarin , dabigitran., Coumadin) 19. If the subject is older than 50 years of age, subjects who have not had a colonoscopy within last 7 years or CT colonography within last 5 years to rule out colon cancer 20. Alarm symptoms of colon cancer such as: 1. Weight loss (>10% unintentional loss of body weight in last 6 months) 2. Blood in the stool (except for clearly documented hemorrhoidal bleed OR colonoscopy excluding colon cancer within the last year for blood in the stool) 3. Anemia (without a full work-up, including a colonoscopy or other tests deemed important) 21. Continued chronic and daily use of prescription laxatives (Ex: Amitiza or Linzess/ linaclotide in the last month) 22. Loose or watery stools > than 3 times per week 23. History of fecal impaction requiring disimpaction in the last 3 months 24. History of laxative abuse (Ex: eating disorders) 25. Use of medications that affect gastrointestinal motility (i.e. resolor, domperidone, reglan, cisapride, anticolonergic drugs, tricyclic antidepressant [Ex: Amitriptyline, Amoxapine, anafranil, asendin, elavil, norpramin/desipramine, doxepin, pamelor/nortriptyline, sinequan, surmontil/trimipramine, tofranil/imipramine or vivactil/protriptyline]) SSRI's are OK 26. Documented untreated pelvic floor dysfunction 27. Colonic organic diseases such as: 1. Current colonic cancer or strictures 2. Connective tissue disease (ex: scleroderma, lupus) 3. Other neurological disorders leading to chronic constipation (Ex: Parkinson's or multiple sclerosis) 28. Dietary intake exceptionally high in plant-based, high fiber foods, including those following a strict vegetarian diet (high fiber foods: fruits, vegetables, beans, whole grains, fortified foods) 29. Consumption of probiotics, prebiotics, or synbiotics without an appropriate 2-week washout period (Ex: Activia, FiberOne products, probiotics supplements such as Align, Pearls, or fiber/prebiotic supplements such as Metamucil, Benefiber, Citrucel, Fiber Choice, Fiber Powder) 30. Intention of using fiber products during the study (other than the study supplement) 31. Known food allergies or hypersensitivities (Ex: the components of psyllium or NTX-1 (corn)) 32. Have a colonoscopy done within the next 5 months Screening Diary 32. Use of laxatives more than twice in the screening period (The following are the ONLY laxatives the subject is allowed to use during the screening period: Ex-lax, senna, miralax and milk of magnesia) 33. Have not completed 11 out of 14 days of symptoms diary at screening 34. Have an average daily IBS-C global symptom score of <2 in the screening period 35. Average Bristol stool scale of more than 4 within the screening period 36. Loose or watery stools with Bristol stool scale of 5 or greater for a total of 6 or more days during the screening period 37. Use of fiber products during the screening period