Which is seen in opioid poisoning –
**Core Concept**
Opioid poisoning is a medical emergency that occurs when an individual ingests an excessive amount of opioids, leading to respiratory depression, sedation, and potentially life-threatening complications. The syndrome is characterized by the presence of miosis, respiratory depression, and altered mental status.
**Why the Correct Answer is Right**
In opioid poisoning, the primary mechanism involves the binding of opioids to mu-receptors in the central nervous system, specifically in the brainstem and spinal cord. This binding leads to the inhibition of neuronal activity in the respiratory centers, resulting in respiratory depression. Additionally, the presence of miosis (pupillary constriction) is a classic sign of opioid poisoning, which is mediated by the activation of parasympathetic nerves and the release of acetylcholine.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not directly related to opioid poisoning. While it may be a potential side effect of other medications or conditions, it is not a characteristic feature of opioid overdose.
**Option B:** This option is incorrect because it is not a specific finding in opioid poisoning. While it may be a symptom of various conditions, it is not a diagnostic hallmark of opioid overdose.
**Option C:** This option is not accurate because it is not a primary effect of opioid poisoning. While it may be a consequence of respiratory depression, it is not a direct result of opioid receptor activation.
**Clinical Pearl / High-Yield Fact**
In cases of suspected opioid poisoning, it is essential to administer naloxone, a specific opioid antagonist, to reverse the effects of the overdose. Naloxone can rapidly improve respiratory function and restore consciousness, making it a crucial medication in emergency settings.
**Correct Answer: B. Miosis.**