There are 3 major types of opioid receptors in the body, and toxicity effects are dependent on the function of each group. There are different preparations of opioids, from synthetic methadone with a 27-hour half-life to shorter-acting, natural instant-release morphine with a half-life of 2 hours. Thus peak serum concentration will be directly linked with the type of ingestion, making history taking critical.
Common clinical features of acute toxicity include altered mental status, miotic pupils, decreased bowel sounds, bradycardia, hypoglycemia, hypotension, and respiratory depression; in severe intoxication, respiratory and cardiac arrest can occur. Toxicity of other medications including acetaminophen may also occur with coingestions.
Resources for opioid prescribing guidelines, as well as nonopioid alternatives, can be found here.
Related topics: Opioid use disorder, Opioid withdrawal syndrome
T40.2X1A – Poisoning by other opioids, accidental (unintentional), initial encounter
241749009 – Poisoning by opiate analgesic drug
- Drug intoxication (alcohol, benzodiazepine, barbiturate, clonidine) – Opioid intoxication notably results in a greater degree of respiratory depression and miosis than these drugs.
- Metabolic encephalopathy (eg, hypoglycemia, hyponatremia, hypernatremia)
- Stroke (particularly brain stem or thalamic)
- Intracranial hemorrhage
- Subarachnoid hemorrhage
- Subdural hematoma
- Epidural hematoma
- Meningitis (viral, bacterial, fungal)
- Hypoxic ischemic encephalopathy
- Nonconvulsive status epilepticus
- Carbon monoxide poisoning
- Neuroleptic malignant syndrome