Chronic or recurrent abdominal pain and erratic bowel disturbance

Tests to make a non-IBS diagnosis
CBC
Routine biochemistry
Celiac serology (tissue transglutaminase antibody, endomysial antibody)
Stool for ova, parasites, and blood
Colonoscopy
Thyroid function
Special tests (depend on symptom pattern)

Positive history for IBS: Make a positive diagnosis

End

No further treatment
Follow-up

Treat comorbid psychiatric disease, e.g., depression
Antidepressants

Fiber/liquids/exercise
Lubiprostone
Linaclotide
Probiotics
Tegaserod
Osmotic laxatives

Anticholinergics
Antidepressants (low dose initially)
Pain clinic

Rifamixin
Eluxadoline
Alosetron
Loperamide
Cholestyramine
Tricyclic antidepressants

Target drugs to specific complaints

Pain

Constipation

Diarrhea

Reassurance
Education
Diet/fiber supplements
Support

Mildly troubled

Persistent specific complaints

Psychiatric component
Difficult

Normal tests and symptoms persist

Exclude:

Colorectal cancer
Inflammatory bowel disease
Metabolic disease