The use of pharmacological treatments for
opioid use disorders, including
methadone,
buprenorphine and
naltrexone has been associated with a reduction in mortality compared with illicit
opioid use. However, these treatments can also contribute significantly to the risk of death. The
opioid agonists
methadone and
buprenorphine achieve clinical efficacy in patients with an
opioid use disorder through suppressing craving and diminishing the effectiveness of illicit
opioid doses, while the antagonist
naltrexone blocks the action of
opioids. Pharmacological differences between
opioid pharmacotherapies then create different temporal patterns of protection and mortality risk, different risks of relapse to illicit
opioid use, and variations in direct and indirect toxicity, which are revealed in clinical and epidemiological studies. Induction onto
methadone and the cessation of oral
naltrexone treatment are associated with an elevated risk of
opioid poisoning, which is not apparent in patients treated with
buprenorphine or sustained-release
naltrexone. Beyond drug-related mortality, these
pharmacotherapies can impact a participant's risk of death.
Buprenorphine may also have some advantages over
methadone in patients with
depressive disorders or
cardiovascular abnormalities.
Naltrexone, which is also commonly prescribed to manage problem alcohol use, may reduce deaths in chronic co-alcohol users. Understanding these pharmacologically driven patterns then guides the judicious choice of drug and dosing schedule and the proactive risk management that is crucial to minimising the risk of death in treatment.