4-(2-Fluorophenyl)-6-methyl-2-(1-piperazinyl)thieno[2,3-D)pyrimidine in the treatment of functional bowel disorder

1. A method for the treatment of an irritable bowel syndrome selected from diarrhea-predominant irritable bowel syndrome, alternating constipation/diarrhea bowel syndrome, and constipation-predominant irritable bowel syndrome wherein said method comprises orally administering, to a patient in need of such treatment, an effective amount of 4-(2-fluorophenyl)-6-methyl-2-( 1-piperazinyl)thieno [2,3-D]pyrimidine or a salt thereof.

2. The method, according to claim 1 , wherein the salt is the hydrochloride monohydrate.

3. The method, according to claim 1 , wherein the disorder is in a female patient.