Which symptom indicates a potential opioid overdose in this patient?

The symptom that indicates a potential opioid overdose is pinpoint pupils. Opioids are known to cause respiratory depression and sedation, which is often accompanied by a characteristic constriction of the pupils, a condition known as miosis. In the context of an opioid overdose, this is one of the classic signs that emergency responders look for, as it can help distinguish opioid-related issues from other types of medical emergencies.

In contrast, rapid heart rate is not typically associated with opioid overdose and can instead be a sign of various other medical conditions or stimulant drug use. Excessive sweating might indicate distress or other medical issues but is not a definitive symptom of opioid overdose. Dilated pupils generally suggest other types of drug intoxication or withdrawal scenarios but are not a symptom associated with opioid overdose, as opioids typically lead to the opposite effect on pupil size.