Naloxone is a medication used to rapidly reverse opioid overdose. It typically starts working within 2-5 minutes after administration and has a half-life of around 30-90 minutes, depending on the dose and the individual’s metabolism. However, it is important to note that naloxone only lasts for a relatively short period of time and therefore may need to be administered multiple times or followed up with further medical treatment to prevent the recurrence of opioid overdose.