Opioid-induced constipation

The best management of opioid-induced constipation is prevention. Patients should be counseled on proper intake of fluids and fiber, and a laxative should be added with chronic opioid use. 

Yuan CS, Foss JF. (2000) Oral methylnaltrexone for opioid-induced constipation. JAm Med Assoc (JAMA) 284 1383-1384. 

Alvimopan, methylnaltrexone bromide Potent antagonists with poor entry into the central nervous system can be used to treat severe opioid-induced constipation without precipitating an abstinence syndrome ... 

Thomas 3 et al Methylnaltrexone for opioid-induced constipation in advanced illness. N Engl 3 Med 2008 358 2332. [PMID 18509120]... 

Reduced motility and secretion can lead to constipation, which is the most common side-effect of chronic opioid treatment (Mancini and Bruera, 1998). Opioid-induced constipation can increase to the stage of megacolon or paralytic ileus. Therefore chronic opioid treatment should be accompanied by concomitant use of laxatives. Besides their peripheral actions, opioids are involved in the central... 

Finally, gastrointestinal distress in the form of nausea and vomiting is quite common with many of the narcotic analgesics. Because of their antiperistaltic action, these drugs can also cause constipation.48 Because this constipating effect can be quite severe, laxatives and stool softeners (see Chapter 27) can be used to prevent opioid-induced constipation in certain people, such as with patients who are at risk for fecal impaction (e.g., people with spinal cord injuries), or with people who are taking opioids for an extended period of time (e.g., patients receiving opioids for treatment of cancer-related pain).36,70... 

The tendency for these drugs to produce constipation is another side effect that could have important implications for patients receiving physical rehabilitation. Opioid-induced constipation is especially problematic in patients with spinal cord injuries or other conditions that decrease gastrointestinal motility. In such patients, opioids are often administered along with laxatives and GI stimulants (see Chapter 27) to minimize the constipating effects and risk of fecal impaction. Therapists should therefore be aware of these constipating effects and help educate patients and their families so that these effects do not result in serious problems. 

Discuss the benefits of senna (as above). He could try starting with one tablet to minimise the adverse effects. If he accepts this suggestion counsel him to take the tablets before bed (as they take 8-10 hours to work). If he is reluctant to try senna explain to him that lactulose is often insufficient alone in treating opioid-induced constipation, and may take 48 hours to work. 

With chronic pain, monitoring tools such as the Brief Pain Inventory, Initial Pain Assessment Inventory, or McGill Pain Questionnaire may be useful. Quality of Ufe must also be assessed on a regular basis in all patients. The best management of opioid-induced constipation is prevention. Patients should be counseled on proper intake of fluids and fiber, and a laxative should be added with chronic opioid use. 

Opioid-induced constipation is more troublesome in older patients, and it should be anticipated by instituting laxative therapy along with the narcotic. A typical laxative regimen consists of psyllium and a stool softener. A mild stimulant laxative such as bisacodyl (Dulcolax) can be added if constipation becomes problematic. 

Thorpe DM Management of opioid-induced constipation. Curr Pain Headache Rep 5(3) 237-240,2001. 

In a phase II, double-blind, randomized, placebo-controlled study of prucalopride 2 or 4 mg/day for 4 weeks in 196 patients with non-cancer pain and opioid-induced constipation, prucalopride improved bowel function [17. The incidence of treatment-related adverse events was 49% with placebo (32/66), 58% with prucalopride 2 mg (38/66), and 50% with prucalopride 4 mg (32/64). The most common adverse events were related to the gastrointestinal system and included abdominal pain and nausea. Abdominal pain was more frequent with prucalopride 4 mg/day (16/64) compared with 2 mg/day (8/66) and placebo (6/66). Pain was the most frequently reported adverse event prucalopride 2 mg/day, 4/66 prucalopride 4 mg/day, 2/64 placebo 3/66. 

Sloots CE, Rykx A, Cools M, Kerstens R, De Pauw M. Efficacy and safety of prucalopride in patients with chronic noncancer pain suffering from opioid-induced constipation. Dig Dis Sci 2010 55 2912-21. 

Thomas J, Karver S, Austin Cooney G, et al. Methylnaltrexone for opioid-induced constipation in advanced iUness. NEJM 2008 358 2332-2343. 

Gastrointestinal constipation and nausea are common. Nausea may be treated with antiemetics, and frequently improves with ongoing therapy. Virtually all patients taking opioids become constipated and do not become tolerant to this side effect. Activation of mu receptors in the gastrointestinal tract slows peristalsis, which promotes further absorption of water and electrolytes in the colon. Patients should be treated prophylactically with stool softeners and/ or laxatives. There is an oral oxycodone/naloxone prolonged-release tablet in clinical trials to counteract opioid-induced constipation, which is often debilitating. 

Methyinaltrexone is FDA-approved for subcutaneous injection in the treatment of opioid-induced constipation in patients with advanced illness who are receiving palliative care and are insufficiently responding to laxative therapy. 

Naloxone The combination of rectal oxycodone 40, 60, or 80 mg/day and rectal naloxone 10, 20, or 40 mg/day has been studied in a randomized, placebo-con-trolled 202 patients with chronic pain [142 ]. The addition of naloxone reduced opioid-induced constipation. 

Methylnaltrexone has been widely used to manage opioid induced constipation and acts by blocking the entry of opioids into cells [199 ]. The common adverse effects include abdominal pain, gas, nausea, dizziness, and diarrhea. The FDA has recommended that patients should stop taking methylnaltrexone if it causes severe diarrhea, vomiting, nausea, or abdominal pain. 

Placebo-controDed studies In a doubleblind, randomized, placebo-controUed trial in 154 patients with advanced iUness and opioid induced constipation a single subcutaneous injection of methylnaltrexone 0.15 or 0.3 mg/kg was compared with placebo [200 "]. The most common adverse events were abdominal pain and flatulence, and three patients had serious adverse events attributed to methylnaltrexone. 

Meissner W, Leyendecker P, Mueller-Lissner S, Nadstawek J, Hopp M, Ruckes C, Wirz S, Fleischer W, Reimer K. A randomised controlled trial with prolonged-release oral oxycodone and naloxone to prevent and reverse opioid-induced constipation. Eur J Pain 2009 13(1) 56-64. 

Lang L. The Food and Drug Administration approves methylnaltrexone bromide for opioid-induced constipation. Gastroenterology 2008 135(1) 6. 

Slatkin N, Thomas J, Lipman AG, Wilson G, Boatwright ML, Wellman C, Zhukovsky DS, Stephenson R, Portenoy R, Stambler N, Israel R. Methylnaltrexone for treatment of opioid-induced constipation in advanced illness patients. J Support Oncol 2009 7(1) 39 6. 

The combination oxycodone/naloxone is an opioid analgesic which may also be used for severe pain in CKD patients. Oxycodone is responsible for the pain-relieving effects, while naloxone reduces opioid-induced constipation. 

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