Pethidine - Adverse Effects

Adverse Effects

The adverse effects of pethidine administration are primarily those of the opioids as a class: nausea, vomiting, sedation, dizziness, diaphoresis, urinary retention and constipation. Unlike other opioids, it does not cause miosis. Overdosage can cause muscle flaccidity, respiratory depression, obtundedness, cold and clammy skin, hypotension and coma. A narcotic antagonist such as naloxone is indicated to reverse respiratory depression. Serotonin syndrome has occurred in patients receiving concurrent antidepressant therapy with selective serotonin reuptake inhibitors or monoamine oxidase inhibitors. Convulsive seizures sometimes observed in patients receiving parenteral pethidine on a chronic basis have been attributed to accumumulation in plasma of the metabolite norpethidine (normeperidine). Fatalities have occurred following either oral or intravenous pethidine overdosage.