1130-0108/2016/108/6/332-363 REVISTA ESPAÑOLA DE ENFERMEDADES DIGESTIVAS COPYRIGHT © 2016 ARÁN EDICIONES, S. L. REV ESP ENFERM DIG (Madrid) Vol. 108, N.º 6, pp. 332-363, 2016 SPECIAL ARTICLE ABSTRACT In this Clinical Practice Guideline we discuss the diagnostic and therapeutic approach of adult patients with constipation and abdominal complaints at the confluence of the irritable bowel syndrome spectrum and functional constipation. Both conditions are included among the functional bowel disorders, and have a significant personal, healthcare, and social impact, affecting the quality of life of the patients who suffer from them. The first one is the irritable bowel syndrome subtype, where constipation represents the predominant complaint, in association with recurrent abdominal pain, bloating, and abdominal distension. Constipation is characterized by difficulties with or low frequency of bowel movements, often accompanied by straining during defecation or a feeling of incomplete evacuation. Most cases have no underlying medical cause, and are therefore considered as a functional bowel disorder. There are many clinical and pathophysiological similarities between both disorders, and both respond similarly to commonly used drugs, their primary difference being the presence or absence of pain, albeit not in an “all or nothing” manner. Severity depends not only upon bowel symptom intensity but also upon other biopsychosocial factors (association of gastrointestinal and extraintestinal symptoms, grade of involvement, and perception and behavior variants). Functional bowel disorders are diagnosed using the Rome criteria. This Clinical Practice Guideline has been made consistent with the Rome IV criteria, which were published late in May 2016, and discuss alarm criteria, diagnostic tests, and referral criteria between Primary Care and gastroenterology settings. Furthermore, all the available treatment options (exercise, fluid ingestion, diet with soluble fiber-rich foods, fiber supplementation, other dietary components, osmotic or stimulating laxatives, probiotics, antibiotics, spasmolytics, peppermint essence, prucalopride, linaclotide, lubiprostone, biofeedback, antidepressants, psychological therapy, acupuncture, enemas, sacral root neurostimulation, surgery) are discussed, and practical recommendations are made regarding each of them. Key words: Irritable bowel syndrome. Constipation. Abdominal discomfort. Adults. Primary care. Digestive diseases. Clinical practice guideline. CONCEPTUAL ASPECTS, IMPACT AND PATHOPHYSIOLOGY 1. Why are irritable bowel syndrome with constipation and functional constipation in the adult jointly approached? Irritable bowel syndrome (IBS) and functional constipa- tion (FC) are two functional bowel disorders (FBDs) (1,2). Therefore, both conditions have in common that their cause is not explained by morphological, metabolic or neurologi- cal changes that may be shown by routine diagnostic tech- niques. IBS may be divided, according to the predominant bowel habit change, into IBS with constipation (IBS-C) and IBS with diarrhea (IBS-D); when both change types (con- stipation and diarrhea) alternate, the condition is referred to as mixed-type IBS (IBS-M), and when bowel habit lies somewhere between constipation and diarrhea the condition is denoted indeterminate IBS (IBS-I) (1,2). While IBS-C and FC are different FBDs from a concep- tual perspective, they may in practice become very similar, even indistinguishable conditions (3-5). In both, constipa- tion is the primary symptom, in association with abdominal Mearin F, Ciriza C, Mínguez M, Rey E, Mascort JJ, Peña E, Cañones P, Júdez J, on behalf of the Sociedad Española de Patología Digestiva (SEPD), Sociedad Española de Medicina de Familia y Comunitaria (semFYC), Sociedad Española de Médicos de Atención Primaria (SEMERGEN) and Sociedad Española de Médicos Generales y de Familia (SEMG). Clinical Practice Guideline: Irritable bowel syndrome with constipation and functional constipation in the adult. Rev Esp Enferm Dig 2016;108:332-363. Received: 18-04-2016 Accepted: 19-04-2016 Correspondence: Javier Júdez. Knowledge Management Department Direc- tor. Sociedad Española de Patología Digestiva (Spanish Society of Digestive Diseases). C/ Sancho Dávila, 6. 28028 Madrid, Spain e-mail: jjudez@sepd.es Note on methodology: This CPG has been developed between January 2015 and December 2015 by a work group made up by experts selected from SEPD, semFYC, SEMERGEN, and SEMG. The Guidelines were revised from December 2015 to April 2016, and made consistent with the Rome IV criteria in May 2016. For a detailed description of the methodological process undertaken dur- ing the development of the present CPG, see: http://www.sepd.es/file/GPC_ SII_E_EF_Metodologia.pdf Additionally to this full version of the CPG, a two-part version is being pub- lished, in coordination, by each channel of expression of semFYC, SEMER- GEN and SEMG (in press). Clinical Practice Guideline: Irritable bowel syndrome with constipation and functional constipation in the adult Fermín Mearin 1 , Constanza Ciriza 2 , Miguel Mínguez 3 , Enrique Rey 4 , Juan José Mascort 5 , Enrique Peña 6 , Pedro Cañones 7 and Javier Júdez 8 , on behalf of the Sociedad Española de Patología Digestiva (SEPD), Sociedad Española de Medicina de Familia y Comunitaria (semFYC), Sociedad Española de Médicos de Atención Primaria (SEMERGEN) and Sociedad Española de Médicos Generales y de Familia (SEMG) 1 Coordinator of the CPG. Roma IV Bowel Disorders Committee. Member of AEG. Centro Médico Teknon. Barcelona, Spain. 2 Functional Gastrointestinal Disorders Group. SEPD. Hospital Universitario 12 de Octubre. Madrid, Spain. 3 Member of AEG and SEPD. Hospital Clínico Universitario. Universitat de Valencia. Valencia, Spain. 4 SEPD. Hospital Clínico Universitario San Carlos. Madrid, Spain. 5 Scientific Department. semFYC. 6 Coordinator. Digestive Diseases. SEMERGEN. 7 Coordinator. Digestive Diseases. SEMG. 8 Knowledge Management Department. SEPD