Opioid analgesics are commonly used to treat moderate to severe pain where use of paracetamol and/or a non-steroidal anti-inflammatory is inadequate in relieving the symptoms. Although beneficial in their actions for relief of moderate to severe pain, inherently their actions at other sites of the body can lead to side effects including nausea, vomiting, sedation and constipation. Nausea, vomiting and sedation typically improve as tolerance in the body builds over time, whereas tolerance to constipation generally occurs slowly, if at all.
Studies estimate that approximately 40% of patients using opioids for analgesia also experience opioid induced constipation (OIC). This estimate increases to over 60% for people using opioid analgesics to treat cancer related pain, mainly due to the doses used being typically higher and for longer periods. In some cases, patients may actually forgo the benefits of opioid analgesia due to the severity of the constipation, leading to sub-optimal pain management outcomes for the patient.
To maximise the potential benefit of opioid analgesia, regular prophylactic use of laxatives should be considered as an essential part of an overarching strategy for optimal pain management. In conjunction with adequate fluid intake, diet and mobility, especially in ‘at risk’ patients such as those with cancer or chronic pain, the elderly, and post-operatively; active management of OIC may improve pain quality and assist in better patient recovery.
Economically, studies suggest that a patient with well controlled symptoms of OIC has a 50% decrease in relative cost burden compared to those with severe symptoms. Moreover, a multi-centre study recently found prophylactic laxatives in oncology patients using opioid analgesia for the first time resulted in a significant reduction in OIC.
Table 1 describes some commonly used laxatives in hospital settings, with evidence suggesting no superiority of any one over another in the management of OIC. Consideration for what to use must be taken in light of the patient’s comorbidities, electrolyte status, and concurrent medications amongst others. Your HPS Pharmacies pharmacist is a reliable reference point for any further information required.
Table 1. Commonly used laxatives.
| Laxative Name | Brand Name | Dosage | Notes |
| Docusate and Senna 50mg/8mg | Coloxyl with Senna Sennesoft |
2-3 tablets once or twice dailyth | Works in 6-24 hours Abdominal cramps, diarrhoea, nausea, rash |
| Lactulose 3.4g/5mL | Actilax, Duphalac, Genlac, GenRx Lactulose, Lac-Dol, Lactocur | 15-30mL once or twice on day one, then 10-25mL dailyth | Works in 24-72 hours Flatulence, cramps, diarrhoea, electrolyte imbalance |
| Macrogol 3350 and Electrolytes | Movicol | 1-3 sachets daily dissolved in 125mL of waterth | Works in 1-4 days for constipation Fluid and electrolyte disturbance, nausea, diarrhoea, cramps, distension |
References:
- Analgesic Expert Group. Therapeutic guidelines: analgesic. Version 6. Melbourne: Therapeutic Guidelines Limited; 2012.
- Rossi S, ed. Constipation. In: Australian Medicines Handbook. AMH 2011. Adelaide: Australian Medicines Handbook; 2011. p. 48.
- Camilleri M. Opioid-induced constipation: challenges and therapeutic opportunities. Am J Gastroentrerol 2011; 106: 835–42.
- Panchal SJ, Muller-Schwefe P, Wurzelmann JI. Opioid-induced bowel dysfunction: prevalence, pathophysiology and burden. Int J Clin Pract. 2007; 61(7): 1181–7.
- Kalso E, Edwards JE, Moore RA, McQuay HJ. Opioids in chronic non-cancer pain: systematic review of efficacy and safety. Pain. 2004; 112(3): 372–80.
- Hjalte F, Berggren AC, Bergendahl H, Hjortsberg C. The direct and indirect costs of opioid-induced constipation. J Pain Symptom Manag. 2010; 40(5): 696–703.
- Ishihara M, Ikesue H, Matsunaga H, Suemaru K, Kitaichi K, Seuetsugu K et al. A multi-institutional study analyzing effect of prophylactic medication for prevention of opioid-induced gastrointestinal dysfunction. Clin J Pain 2012; 28(5): 373–81.