Naloxone, aka Narcan or Nyxoid which can be administered as a nasal spray or by injection, can quickly reverse an overdose from opioids, including heroin, fentanyl, oxycodone, hydrocodone, codeine, and morphine. (It will not work on overdoses from cocaine, methamphetamine, or other non-opioid drugs.)

Naloxone is a TGA approved medicine used ONLY to quickly reverse an opioid overdose.

Naloxone is a opioid antagonist that works by  It

Naloxone should be used as soon as possible to treat a known or suspected opioid overdose emergency if there are signs of slowed breathing, severe sleepiness or the person is not able to respond (loss of consciousness). Once naloxone has been given the patient must receive emergency medical care straight away, even if they wake up.