Opioid-dependent error processing.

OBJECTIVE

To evaluate error processing in contrasting opioid treatment samples by finding the relative risk of fatal dosing errors leading to opioid overdose in a controlled cohort of detoxified patients with opioid dependence.

METHODS

Data linkage was performed between the Western Australian deaths register and recorded admissions to the Perth Naltrexone Clinic and community-based methadone program. Death register and corresponding data of coronial findings for all the patients who were treated with rapid opioid detoxification under sedation and oral naltrexone were compared with corresponding data for all the patients who were prescribed methadone over a 2-year period.

RESULTS

Data for naltrexone-treated patients (n = 1,097) and community-based methadone-treated patients (n = 2,520) showed mortality rates to be 2.6 percent per year for naltrexone treatment when compared with O.7 percent for methadone treatment (p < 0.001). This was due to 4.3 times the relative risk of death from opioid toxicity for naltrexone-treated patients (p < 0.001).

CONCLUSIONS

Naltrexone increases vulnerability to overdose as enhanced opioid effects following neuroanatomical blockade can reverse behavioral tolerance and lead to greater fatal dosing errors on reinstatement of opioid dependence.