Centrally Targeted Pharmacotherapy for Chronic Abdominal Pain: Understanding and Management

Abstract

Chronic abdominal pain has a widespread impact on the individual and the society. Identifying and explaining mechanisms of importance for the pain experience within a biopsychosocial context are central in order to select treatment that has a chance for symptom reduction. With current knowledge of brain-gut interactions, chronic abdominal pain, which mostly appears in functional gastrointestinal disorders, to a large extent involves pain mechanisms residing within the brain. As such, the use of centrally targeted pharmacotherapy as an effective treatment option is obvious in a selected number of patients. The antidepressants are most common, but also other classes of medications can be used, either alone or in combination. The latter option refers to when there is insufficient effect of one drug alone or side effects limiting dosage, and when combined in lower doses, certain drugs give rise to augmentation effects. This chapter outlines basic mechanisms of importance for the understanding of chronic abdominal pain and the pharmacologic treatment options.

Antidepressants vs. Placebo for the Treatment of Functional Gastrointestinal Disorders in Adults: A Systematic Review and Meta-Analysis

“…Consistently, recent systematic reviews and meta-analysis indicated that antidepressants were effective for IBS (17, 18). Clinical reviews also supported the efficacy of antidepressants for patients with FD (10), functional esophageal disorders (19), and functional abdominal pain (20). Nevertheless, compared carefully, the studies included and the effect sizes in each review still differed.…”

“…According to the recommendations of the Cochrane Collaboration (20), the risk of bias was assessed from eight aspects: random sequence generation (selection bias), allocation concealment (selection bias), blinding of participants and of personnel/care providers (performance bias), blinding of outcome assessor (detection bias), incomplete outcome data (attrition bias), selective reporting (reporting bias), group similarity at baseline (selection bias), and other bias (funding bias). We explicitly judged each of these eight criteria as exemplifying a low, high, or unclear risk of bias.…”

“…Nevertheless, evidence yielded from those studies was contradictory. Systematic reviews and clinical guidelines before 2008 basically found no clear evidence of benefit for antidepressants (14–16), while updated reviews generally indicated that they were effective for the treatment of IBS (17, 18), FD (10), FCP (19), and functional abdominal pain (20). However, unlike the real world, most researches only focused on one specific subtype of FGIDs, while the comorbidity with other subtypes of FGIDs and mental disorders often was not accounted for.…”

How to manage postcholecystectomy abdominal pain

“…Following thorough investigation, most patients will not have a structural cause identified and will be classified as having functional biliary-type, the detailed management of which is outside the remit of this review. Low-dose tricyclic antidepressants have shown benefit in reducing overall symptomatology and pain indices 47. Additionally in a recent pilot study, the antidepressant duloxetine, a selective and potent balanced dual 5-hydroxytryptamine (5-HT) and serotonin–norepinephrine reuptake inhibitor, was found to be beneficial in 90% (n=10) of patients with suspected SOD 48…”