REVIEW Chronic constipation in adults Sibanda M, BPharm, MPharm, MSc Pharmacology, MBA, Meyer JC, MSc(Med) Pharmacy, PhD (Pharmacy), Maponya M, BPharm, Motha T, BPharm School of Pharmacy, Sefako Makgatho Health Sciences University Correspondence to: Hannelie Meyer, e-mail: [email protected] Keywords: chronic constipation, adults, pharmacological treatment, dietary modification, behaviour modification, patient education Abstract Chronic constipation is a prevalent gastrointestinal motility disorder, which may be primary (idiopathic) or due to secondary causes. Although chronic constipation is not a life-threatening condition, it has a negative impact on patients’ daily activities and quality of life. This article examines chronic constipation in adult patients with emphasis on the main causes, diagnosis and treatment options, including the pharmacological and non-pharmacological management. Patient education and counselling to improve treatment outcomes are also discussed. © Medpharm S Afr Pharm J 2018;85(1):34-42 Introduction Main causes and risk factors for constipation Constipation is a very common gastrointestinal disorder in many Constipation can be primary (idiopathic) or secondary due to other patients across the world.1,2 It is generally defined as fewer than causes.10 Primary constipation is classified into three main types, three bowel movements per week and is characterised as failure namely normal-transit constipation, slow-transit constipation to completely remove stool, decreased frequency and lack of and anorectal (pelvic floor) dysfunction.10,11 Normal-transit satisfaction after defecation.1 Chronic constipation can present constipation, also known as functional constipation is the most as either disorders of transit (normal or slow) or disorders of common type of constipation, with stool passing through the evacuation, or both. These are related, as disorders of transit can colon at a normal rate.11 Patients with normal-transit constipation develop secondary to disorders of evacuation, while disorders feel constipated and complain of difficulty with evacuation, hard of evacuation can follow from disorders of transit.2 While it is stools, bloating, abdominal pain or discomfort.10 It must be noted not a life-threatening condition and can be managed at primary that there is an overlap between normal-transit constipation healthcare level, it is associated with a negative impact on the and irritable bowel syndrome (IBS) constipation.10 Slow-transit quality of life for many patients and has considerable economic constipation, which is common amongst females, involves a costs associated with it.2,3,4 Known complications of constipation lengthened delay in the passage of stool through the colon.10 are faecal incontinence, haemorrhoids, anal fissure, organ prolapse, faecal impaction and bowel obstruction, bowel perforation and Anorectal (pelvic floor) dysfunction is characterised by poor stercoral peritonitis.5 coordination of the pelvic muscles and anal sphincter muscles, presenting as a defecation disorder.10 In many patients with The prevalence of constipation is estimated to be 20% in the normal or slow colonic transit, pelvic floor dysfunction may general population; this is however dependent on the definition contribute to constipation, presenting as difficulty in expelling 6 used and population being studied. Cases of constipation are stools from the rectum.10 In the case of slow-transit constipation, deemed to generally increase with age and the prevalence of patients have substantial impairment of propulsive colonic motor 3,7 constipation is higher in non-whites as well as in women. activity, and reduced colonic responses, particularly after a meal According to literature, chronic constipation is estimated to have and on awakening in the morning.10 affected about 2% to 27% of the population in North America.4,8 In China, the prevalence of constipation (8%) is lower when The causes of secondary constipation vary from organic compared to the United States of America, Canada and European endocrine to metabolic neurological causes, including diabetes countries and this can be highly attributed mostly to their diet.9 mellitus, hypothyroidism, chronic renal insufficiency, colorectal Paradoxically, Chinese people in the rural areas presented with cancer, spinal cord injury, Parkinson’s disease, paraplegia and more cases of constipation than that of urban areas, also those multiple sclerosis.10 A low fibre diet, dehydration and an inactive that were uneducated presented with more cases of constipation lifestyle are also considered as secondary causes of constipation. than the educated.9 Other secondary causes of constipation may include medication S Afr Pharm J 34 2018 Vol 85 No 1 REVIEW and anorectal problems such as anal fissure and inflammatory Box I. Rome III criteria classification system for chronic constipation10,13 10 bowel disease. Criteria fulfilled for the last 3 months and symptoms onset at least 6 months prior to diagnosis There are a number of factors reported to be associated with • Presence of ≥ 2 of the following symptoms: constipation, however these associations do not necessarily ◦ Lumpy or hard stools in ≥ 25% of defecations indicate causation.12 Risk factors for constipation vary from lack ◦ Straining during ≥ 25% of defecations of physical activity, which is associated with a two-fold increased ◦ Sensation of incomplete evacuation for ≥ 25% of defecations Sensation of anorectal obstruction/blockage for ≥ 25% of defecations risk of constipation, to stressful life events and depression, ◦ ◦ Manual manoeuvres to facilitate ≥ 25% of defecations (digital physical abuse and sexual abuse, use of medication, lower manipulation, pelvic floor support) socio-economic status and lower education.2,3,12 Advanced age, ◦ < 3 evacuations per week poor food intake with low dietary fibre and poor fluid intake are • Loose stools rarely present without the use of laxatives common predisposing factors to constipation. However, a lack of • Insufficient criteria for irritable bowel syndrome fluid intake may play a greater role in the development of faecal In addition to the Rome III criteria, the Bristol Stool Form Scale impaction, rather than constipation.7,11 Female sex is another risk (BSFS) is a useful visual aid designed to assist in the evaluation factor as there is evidence of a higher incidence of self-reported of patients with constipation (Box II).4,10 This tool is particularly constipation in women.2 Table I shows examples of medicines useful in patients with self-reported constipation as it uses visual commonly known to be associated with secondary constipation. descriptors to illustrate common stool forms and regularity on a 7-point scale.10 Box II shows that constipation is indicated by 3,6 Table I. Classes of drugs commonly associated with constipation Types 1 and 2 stool descriptions, Types 3 and 4 are considered Pharmacological class Examples normal, being easy to defecate with no excess liquid, while Types 5HTз receptor antagonists Ondansetron 5, 6 and 7 represent diarrhoea.4 The form of stool is dependent Analgesics on the time the stool spends in the colon, making the BSFS a Opiates Morphine reliable transit time indicator.10 Type 1 stool indicates the longest Nonsteroidal anti-inflammatory drugs Ibuprofen time spent in the colon while the least time spent in the colon is Anticholinergic agents Belladona represented by Type 7 stool.10 Tricyclic antidepressants Amitriptyline Antipsychotics Chlorpromazine Box II. Use of the Bristol Stool Form Scale in the diagnosis of Antihistamine Diphenhydramine constipation4,10 Antispasmodics Dicyclomine Transit Type Description of stool Indication Antiparkinsonian drugs Benztropine time Sympathomimetics Longest Separate hard lumps like nuts Beta-adrenergic receptor agonists Ephedrine, terbutaline 1 (difficult to pass) Anticonvulsants Carbamazepine Constipation Antihypertensives 2 Sausage shaped but lumpy Calcium channel blockers Verapamil, nifedipine Diuretics Furosemide Like a sausage but with cracks on its Centrally acting alpha-agonist Clonidine 3 surface Antiarrhythmic Amiodarone Normal Beta-adrenoceptor antagonist Atenolol Like a sausage or snake, smooth Cation-containing agents 4 and soft Aluminium Antacids, sucralfate Calcium Antacids, supplements Soft bobs with clear-cut edges Iron supplements Ferrous sulphate in the colon spent Time 5 (passed easily) Bismuth Antacids Lithium salts Antipsychotics Fluffy pieces with ragged edges, 6 Diarrhoea Chemotherapy agents a mushy stool Vinca alkaloids Vincristine Alkylating agents Cyclosphosphamide Watery, no solid pieces, entirely liquid Least 7 Miscellaneous compounds Barium sulphate Oral contraceptives Additional tests for constipation include blood tests, imaging tests Diagnosis of constipation and functional tests. Blood tests have shown inefficiency in the diagnosis of constipation, however blood tests may be indicated The Rome III criteria classification system (Box I) is a widely for hospital in-patients whose medical history leads to a condition recognised tool, used for the diagnosis of chronic constipation, that could be causing the constipation.14 Barium imaging tests using standardised symptom based criteria.13 The tool relies on such as colonoscopies and barium enemas are used as diagnostic organs where the symptoms are presumably produced.10,13 tools of constipation. A colonoscopy is recommended for patients S Afr Pharm J 35 2018 Vol 85 No 1 REVIEW 2-week Detailed patient history (nature