The deaths of a man and a woman, who are both in their 40s, at a Basildon address yesterday has sparked an urgent warning to drug users by Essex Police.

Officers identified the presence of etonitazene, a harmful and synthetic opioid, which is 40 times more powerful than fentanyl and up to 80 times more stronger than morphine.

What are synthetic opioids?

Synthetic opioids are self-made drugs that which replicate the effects of natural opioids, such as heroin, to produce pain relief effects. This includes fentanyl.

Most of these drugs are classified as class A – meaning they are illegal to have, give away or sell.

They are “occasionally added to illicit drugs, like heroin, to enhance the potency”.

How do people take synthetic opioids?

The drugs can be injected, sniffed, swallowed, heated or inhaled.

By sniffing or inhaling the class A drugs may cause damage to the throat and nose, whereas injecting can harm the and veins and arteries, leading to infections, blood clots and death of a body tissue – usually a finger, toe or limb.

As medical versions, including fentanyl, are available as solutions for injection, this brings a danger to sharing needles, and this can lead to the development of serious tissue infections, as well as spreading viral infections, such as HIV.

What are the risks of synthetic opioids?

They are effective at very small doses, which makes them addictive and easy to take too much, which increases the risk of respiratory arrest in users.

Lower doses of opioids can make people feel sleepy, but higher doses can also slow down a user’s heart rate, which can lead to death.

Taking in too much can lead to bad and harmful effects, including constipation, itching, nausea, retching, loss of consciousness and coma.

Where can people get help for a synthetic opioid addiction?

Medical professionals recommend individuals to get help from a drug rehab facility.

To find out where the nearest drug treatment services are located, the NHS has a dedicated service search page on their website: www.nhs.uk/Service-Search/other-services/Drug%20treatment%20services/LocationSearch/340.