There are many known side effects of anticholinergic antispasmodics and TCAs, such as: headache, dry mouth, cough, blurred vision, constipation, dysuria; postural hypotension; tachycardia, decreased libido; erectile failure; increased sensitivity to the sun; weight gain; sedation, increased sweating. Loperamide side effects include: Stomach ache, nausea, vomiting, bloating, constipation, dry mouth, drowsiness or dizziness, and cholestyramine has been known to cause constipation, heartburn, indigestion, nausea, vomiting, and stomach pain, and has caused tumors in animal studies. These profiles suggest the need for a safer, more tolerable and more comprehensive therapy for IBS.