A multi-institutional study analyzing effect of prophylactic medication for prevention of opioid-induced gastrointestinal dysfunction
The Clinical Journal of Pain, 05/11/2012

Ishihara M et al. – Authors showed evidence for the effectiveness of premedication with laxatives for prevention of opioid–induced constipation. However, premedication with dopamine D2 blockers was not sufficient to prevent nausea or vomiting.

• A multi–institutional retrospective study was carried out, in which 619 eligible hospitalized patients receiving oral opioid analgesics for cancer pain were enrolled from 35 medical institutions.
• The primary endpoint was the incidence of opioid–induced side effects in patients receiving prophylactic medication.
• Odds ratios of the incidence of adverse reactions in the absence or presence of premedication obtained from several institutions were subjected to a meta–analysis.

• Among 619 patients, the incidence of constipation was significantly lower in patients receiving laxatives, including magnesium oxide, as premedication than in those without them (34% vs. 55%, odds ratio=0.432, 95% confidence interval=0.300–0.622, P<0.001).
• However, the incidence of nausea or vomiting was similar regardless of prophylactic medication with dopamine D2 blockers.
• The results of the meta–analysis revealed that prophylactic laxatives significantly reduced the incidence of constipation (overall odds ratio=0.469, 95% confidence interval=0.231–0.955, P=0.037), whereas dopamine D2 blockers were not effective in preventing opioid–induced nausea or vomiting.