The aim of this study is to assess the effect of orally administered TU-100 (5 g three times daily [TID]) as compared to placebo on abdominal bloating rating in female IBS patients.

Inclusion Criteria:

• Meet Rome III criteria for IBS (any subtype)
• Female aged 18 to 65 years, inclusive
• If of childbearing potential, prepared to use suitable forms of contraception throughout the study and for 30 days after the last dose i.e., hormonal contraceptives (such as oral contraceptives, Depo-Provera, NuvaRing, Essure), condoms used with a spermicide, an intrauterine device, or abstinence. Females are not considered to be of childbearing potential if they are naturally postmenopausal (no menses for at least 1 year and, if < 55 years of age, have a documented follicle-stimulating hormone [FSH] level of ≥ 35 mIU/mL) or have documentation of surgical sterility
• Have a BMI between 18 and 30 kg/m2, inclusive
• Have a negative pregnancy urine screening at Visit 1, if of childbearing potential
• Able to provide written consent
• Able to take oral administration of the testing medications
• Have a self-reported average abdominal bloating rating (>3 daily ratings over the preceding 7 days) equal or greater than 4 on a numerical scale of 0 to 20.

Exclusion Criteria:

• Have a structural or metabolic disease or condition that affects the GI system, excluding asymptomatic gallstones or uncomplicated gastroesophageal reflux disease, or any medical condition that may be a cause of constipation or diarrhea (e.g., hypothyroid status, poorly controlled diabetes, diabetic neuropathy or autonomic neuropathy)
• Be taking any medication that, in the opinion of the Principle Investigator (PI), has potential to alter GI transit. A full list of prohibited medications is provided in the protocol. Have history or presence of any chronic lung disease
• Have presence of hepatic dysfunction, jaundice, or abnormal serum alanine aminotransferase (ALT) or aspartate aminotransferase (AST) values exceeding 2.5 x upper limit of normal
• Currently pregnant or lactating
• Have a positive urine drug test at screening (subjects who initially test positive will be allowed one retest)
• Be a known substance abuser or be considered to be an alcoholic not in remission
• Have participated in another clinical study in the past 30 days
• Use of supplemental ginger, ginseng, or Zanthoxylum fruit for 2 weeks prior to randomization and throughout the course of the study.
• Have a history of allergic reaction to ginseng, ginger or Zanthoxylum fruit
• Be clinically lactose-intolerant
• Have any other condition that, in the opinion of the PI, causes the subject to be unsuitable to participate
• Have taken antibiotics in the last 3 months
• Have had gastroenteritis ("stomach flu") in the last 3 months
• Have taken probiotics in the last 3 months (over-the-counter [OTC] products or supplements only; food products such as yogurts are permitted).