Dose Escalation Trial of Traditional Chinese Medicine for Irritable Bowel Syndrome (TCM- IBS)

The Specific aims of the project are:

• To determine whether a 20- herb formulation improves pain/ discomfort and disturbed bowel frequency in patients with Irritable Bowel Syndrome who have been disappointed with current conventional Western medicine.
• To identify an optimal dosage of the 20- herb formulation that is safe and well tolerated for up to 8 weeks of treatment, among 2 dosages. This is determined by relief of symptoms of IBS in a dose escalation, placebo-controlled double- blind randomized clinical trial, in conjunction with indices of safety and tolerability.

Inclusion criteria

• Age 18- 75
• All IBS patients attending the Gastroenterology Clinic of the Prince Of Wales Hospital of Hong Kong.
• IBS diagnosed by Rome III criteria:

• Recurrent abdominal pain or discomfort at least three days per month in the previous three months
• Symptoms onset at least six months prior to diagnose
• Pain or discomfort associated with two or more of the following:

• Improvement with defecation
• Onset associated with change in frequency of stool
• Onset associated with a change in form (appearance) of stool
• Normal colonic evaluation (colonoscopy or barium enema) in past 5 years
• No "global symptom improvement" as rated by patients (see below) at screening and during the two- week run- in period to baseline
• Normal full blood count, liver function test and renal function test.

• Informed written consent for participation into study.
• Ethical approval will be obtained from the Joint CUHK-NTEC Clinical Research Ethics Committee as well as the IRB of UMB.

Exclusion criteria

• Past or present history of organic disease of gastrointestinal tract (e.g. colorectal cancer, advanced colonic polyp, celiac disease, inflammatory bowel disease, peptic ulcer and previous gastrointestinal surgery). (Note: those with polyps removed during colonoscopy can be included, as long as no known polyps remained.
• Systemic diseases that cause diarrhea or constipation (e.g. thyroid disease, diabetic neuropathy)
• Lactose intolerance
• Severe liver disease (e.g. cirrhosis, chronic active hepatitis)
• Renal impairment (serum creatinine level > 150mmol/L)
• Women who are pregnant, lactating or not practicing proper contraception
• Known hypersensitivity to herbal medicine
• Concommitant use of prescription antidepressant medication
• Current alcoholism and drug use
• Current psychiatric illness or dementia
• Fever or severe illness at baseline (week 0).