NSW Health has issued a public health warning after about 20 people suffered severe opioid overdoses in the Penrith area in the past month.
An investigation revealed nitazenes were found in drug samples related to a cluster of overdoses reported in Nepean Blue Mountains Local Health District.
A NSW Health spokesperson said nitazenes were potent synthetic opioids which could be stronger than fentanyl and hundreds of times more potent than heroin.
The drug was more likely to cause people to decrease or stop breathing than other opioids.
NSW Health chief addiction medicine specialist Hester Wilson said drugs containing strong opioids could cause severe overdose or death.
“Nitazenes are extremely potent,” Dr Wilson said.
“It is important that people recognise the signs of an opioid overdose early and know how to respond.
“Opioids such as heroin can cause pinpoint pupils, drowsiness, loss of consciousness, slowed breathing or snoring, skin could turn blue or grey and they could be life-threatening.
“One of the dangers of illicit drug supply is the strength and contents of the substance you are getting is unknown and could be inconsistent.
“In light of this detection, people who use drugs such as heroin should carry naloxone.”
Take home naloxone is a lifesaving measure, which could temporarily reverse an opioid overdose, including with nitazenes.
Nitazenes can last longer in the body than heroin and naloxone. Higher and repeated doses of naloxone are often required, as well as hospital treatment.
Anyone who uses naloxone should call triple-zero for an ambulance immediately after use for follow-up care.
NSW Health assured that people would not get into trouble for seeking medical care.
“If you feel unwell, or if your friend feels unwell, do something about it,” a spokesperson said.
Take home naloxone is available as an easy-to-use nasal spray or injection from some pharmacies and other health services.
Anyone who has concerns about adverse effects from drugs should contact the NSW Poisons Information Centre.