Constipation is common, impairs quality of life and consumes considerable health-care resources
Recognition of whether constipation is primary or secondary is key for appropriate management
A detailed history and physical examination including digital rectal examination is important and can identify an evacuation disorder
Physiological tests such as colonic transit assessment, anorectal manometry and the balloon expulsion test can facilitate stratification of patients with different constipation subtypes
Newer drugs, such as linaclotide and lubiprostone, laxatives, and biofeedback therapy can considerably improve symptoms in patients with chronic constipation
Constipation is a heterogeneous, polysymptomatic, multifactorial disease. Acute or transient constipation can be due to changes in diet, travel or stress, and secondary constipation can result from drug treatment, neurological or metabolic conditions or, rarely, colon cancer. A diagnosis of primary chronic constipation is made after exclusion of secondary causes of constipation and encompasses several overlapping subtypes. Slow-transit constipation is characterized by prolonged colonic transit in the absence of pelvic floor dysfunction. This subtype of constipation can be identified using either the radio-opaque marker test or wireless motility capsule test, and is best treated with laxatives such as polyethylene glycol or newer agents such as linaclotide or lubiprostone. If unsuccessful, subspecialist referral should be considered. Dyssynergic defecation results from impaired coordination of rectoanal and pelvic floor muscles, and causes difficulty with defecation. The condition can be identified using anorectal manometry and balloon expulsion tests and is best managed with biofeedback therapy. Opioid-induced constipation is an emerging entity, and several drugs including naloxegol, methylnaltrexone and lubiprostone are approved for its treatment. In this Review, we provide an overview of the burden and pathophysiology of chronic constipation, as well as a detailed discussion of the available diagnostic tools and treatment options.
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The authors would like to thank H. Smith (Medical College of Georgia, Augusta, Georgia, USA) for technical and secretarial assistance.
S.S.C.R. serves on the advisory boards of Forest Labs, Salix, Synergy and Takeda, and has reviewed research grants from Forest Labs and Medtronic. K.R. and T.P. declare no competing interests.
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Rao, S., Rattanakovit, K. & Patcharatrakul, T. Diagnosis and management of chronic constipation in adults. Nat Rev Gastroenterol Hepatol 13, 295–305 (2016). https://doi.org/10.1038/nrgastro.2016.53
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