CLINICAL REVIEWSMyths and Misconceptions About Chronic ConstipationMüller-Lissner, Stefan A. M.D.; Kamm, Michael A. M.D., F.R.C.P.; Scarpignato, Carmelo M.D., D.Sc., F.A.C.G.; Wald, Arnold M.D., F.A.C.G.Author Information Park-Klinik Weissensee, Berlin, Germany; St. Marks Hospital, London, UK; Laboratory of Clinical Pharmacology, Department of Human Anatomy, Pharmacology and Forensic Sciences, University of Parma, Parma, Italy; and University of Pittsburgh Medical Center, Pittsburgh, USA Reprint requests and correspondence: Stefan Mueller-Lissner, M.D., Abteilung Innnere Medizin, Park-Klinik Weissensee, Schönstrasse 80, 13086 Berlin, Germany. Received July 1, 2004; accepted July 26, 2004. American Journal of Gastroenterology: January 2005 - Volume 100 - Issue 1 - p 232-242 Buy Abstract There are many strongly held beliefs about constipation that are not evidence based. The purpose of this review is to address these beliefs concerning various aspects of constipation. There is no evidence to support the theory that diseases may arise via “autointoxication,” whereby poisonous substances from stools within the colon are absorbed. Dolichocolon, defined as an elongated colon, should not be seen as a cause of constipation. The role of sex hormones altering gut function during the menstrual cycle appears to be minimal. During pregnancy they may play a role in slowing gut transit. Hypothyroidism can cause constipation, but among patients presenting with constipation, hypothyroidism is rare. A diet poor in fiber should not be assumed to be the cause of chronic constipation. Some patients may be helped by a fiber-rich diet but many patients with more severe constipation get worse symptoms when increasing dietary fiber intake. There is no evidence that constipation can successfully be treated by increasing fluid intake unless there is evidence of dehydration. In the elderly constipation may correlate with decreased physical activity, but many cofactors are likely to play a role. Intervention programs to increase physical activity as part of a broad rehabilitation program may help. It is unlikely that stimulant laxatives at recommended doses are harmful to the colon. A proportion of patients with chronic constipation is dependent of laxatives to achieve satisfactory bowel function, but this is not the result of prior laxative intake. Tolerance to stimulant laxatives is uncommon. There is no indication for the occurrence of “rebound constipation” after stopping laxative intake. While laxatives may be misused, there is no potential for addiction. © The American College of Gastroenterology 2005. All Rights Reserved.