Pain Medications and Constipation: A Mean Cycle

Consider how many times we have worked with a patient who refuses to participate in rehabilitation or cancels an appointment because of constipation. Also recall the high number of patients we treat who are in chronic pain and who are also likely taking an opioid medication for pain management. A well-known side effect of opioids is constipation, which can create a viscous cycle: taking the medication can mean having to strain to pass stool, or being bloated which can aggravate an already painful state. Not taking pain medications can increase pain levels, potentially decreasing physical activity levels, another cause for poor bowel function. A recent research article sheds light on this problem, pointing out that, despite a failure of medications in positively treating their constipation, patients are willing to continue on the current course of treatment.

The on-going longitudinal study in the USA, Canada, Germany, and the UK aims to assess the burden of opioid-induced constipation (OIC) in patients who have chronic pain that is not cancer-related. Patients were using at least 30 mg of opioids per day for more than four weeks and had self-reported opioid-induced constipation. For the 493 patients who met the inclusion criteria, retrospective chart reviews, on-line patient surveys, and physician surveys were utilized. Outcomes tools included the Patient Assessment of Constipation-Symptoms, Work Productivity and Activity Impairment Questionnaire-Specific Health Problem, EuroQOL 5 Dimensions, and Global Assessment of Treatment Benefit, Satisfaction, and Willingness to Continue. 62% of the patients were female, mean age in males and females was 52.6.

Patients complained of bowel dysfunction including abdominal pain and bloating, painful straining to defecate and having flatulence, rectal pain and bleeding, headaches, and having hard stools that were difficult to pass. Most of the patients (83%) wanted to have at least one bowel movement (BM) per day, yet the mean reported BM was 1.4 per week without use of laxatives, and 3.7 BM with use of laxatives. Natural or behavioral therapies were used by 84%, and 60% of the patients used at least 1 over-the-counter (OTC) laxative, 24% used 2 or more OTC laxatives, and 19% used one or more prescription laxatives. Unfortunately, 94% of the patients reported inadequate response to laxative use.

Current employment rates for the sample population was 27%, and of these patients, the average reports of missed work due to constipation issues was 4.6±11.9 hours of work over the past 7 days. Even worse, from a pain-management perspective, 49% of the patients reported "…moderate to complete interference with pain management resulting from their constipation." The authors conclude the following: "The prevalence of these symptoms suggests that patients may be undertreating their OIC and/or that the currently utilized therapies for the treatment of OIC may be lacking in efficacy and tolerability." Can we conclude that the under-treatment applies to a lack of pelvic rehabilitation intervention? Granted, opioid-induced constipation by nature of its effects on the gut will in turn affect peristalsis and hydration of stool. However, if a patient learns techniques to stimulate bowel activity, how to manage abdominal bloating and pain, and how to affect the nervous system in a positive way, perhaps less work (and leisure) time would be lost.

If you are interested in learning more about constipation, we have one opening in the PF2A St. Louis course taking place in early October. If you have already taken PF2A, and want to expand your knowledge and your skill set, join faculty member Lila Abbate in her Bowel Pathology and Function continuing education course in California in early November. Course topics include over-the-counter products and medications affecting bowel health, constipation and fecal incontinence, internal vaginal and rectal muscle mapping, and a balloon-manometry lab- a lab that therapists are thrilled to have offered in an Institute course!