Specific Opioid Toxicities and Overdose Complications: 

• Dextromethorphan
   -Serotonin syndrome: triad of AMS/agitation, autonomic instability including hyperthermia, and neuromuscular abnormality with clonus/hyperreflexia

• Fentanyl
  -Chest wall rigidity in thoracic and abdominal musculature: difficult to ventilate, possible reversal with narcan

• Hydrocodone and oxycodone 
  -Often contains acetaminophen 
  -Some suggestion oxycodone leads to prolonged QTc

• Loperamide 
  -National poison center: 71% increase in loperamide overdose cases from 2011 to 2015 
  -Often taken to aid withdrawal symptoms (occasionally as recreational high) 
  - Cardiac dysrhythmias: prolonged QT and QRS widening (K+ and Na+ channel blockade) 
          -Treatment: Mag sulfate, Na bicarb, isoproterenol, overdrive pacing 

• Methadone 
  -Very long acting Half life 27 +/- 12 hours 
  -QTc prolongation

•  Tramadol 
  -Seizures, typically occur in first 24 hours after using medication (~80-90%) 
  -GTC seizures, more common in those also using etoh, anti-depressants, anti-psychotics, other substances

References: 
-Boostani, Reza and Siavash Derakhshan. “Tramadol induced seizure: A 3-year study.” 
-Caspian J Internal Medicine. 2012 Summer; 3(3): 484–487. Burns, G et al. “Could chest wall rigidity be a factor in rapid death from illicit fentanyl abuse?” Clinical Toxicology. 2016 Jun;54(5):420-3 
-Eggleston et al. “Loperamide Abuse Associated With Cardiac Dysrhythmia and Death.” Annals of Emergency Medicine. Jan 2017 Vol 69 Issue 1. 83-86