[Symptomatic therapy of irritable bowel syndrome.  Which drug for which symptoms?]. 
After establishing the diagnosis, reassuring the patient, and applying non-drug measures, pharmacotherapy forms a major pillar in the treatment of IBS, despite the fact that because the pathophysiology is still unknown, we have no causal drug treatment available.  In the first instance, medication is a recommended supportive measure for application during the symptom-free intervals.  It is oriented to the patient's leading complaints, and is directed towards the regulation of bowel movements, treatment of flatulency, and amelioration of painful motility disorders (e.g. spasms).