Billionaires shouldering the blame for the US opioid crisis have now come under fire for making money off an overdose treatment.

The Sackler family, who own the company which makes the addictive high-strength painkiller OxyContin, are no strangers to scandal.

Facing thousands of lawsuits accusing them of causing soaring drug overdose rates in the US, they now stand accused of profiting from OxyContin's antidote.

A UK-based company called Mundipharma, owned by the Sacklers, is selling a nasal spray drug named naloxone for around £38 ($50) a dose.

It can be lifesaving for people who have overdosed on painkillers. Experts said it was 'deeply cynical' for the wealthy empire to be selling both.

Mundipharma's Nyxoid nasal spray is reportedly being sold in Europe for more than £38 ($50) per dose – it is the treatment for patients who overdose on a drug called OxyContin, which is made by a company owned by the same family

Numbers of opioid overdose deaths have soared since OxyContin hit the market in 1996, from just 3,442 in 1999 to 17,029 in 2017, official figures show

'If they were trying to find a solution, they would just distribute naloxone for free,' Stephen Wood, a Harvard University professor, told the Associated Press.

'They could use all that money they made off opioids to help support a program where they are giving away this life-saving medication.'

The Sackler family's OxyContin-producing company, Purdue Pharma, is privately-owned and not listed on a stock exchange but has an estimated annual revenue of $3billion (£2.25bn).

Mundipharma, which is based in the English city of Cambridge, is selling its naloxone nasal spray, named Nyxoid, in Europe.

At a medical conference in Italy in October it advertised it with the slogan 'Be prepared. Get naloxone. Save a life,' AP reported.

OxyContin is a high-strength painkiller which is addictive and can cause overdoses. The drug, which contains the generic chemical oxycodone hydrochloride, is made by the company Purdue Pharma

Mundipharma promoted Nyxoid, a new brand of opioid overdose reversal medication, at a medical conference in Italy with the phrase 'Be prepared. Get naloxone. Save a life'

HOW IS OXYCONTIN IMPLICATED IN THE US OPIOID CRISIS? Purdue Pharma and its owners the Sackler family are offering a settlement of up to $12billion (£9bn) to resolve more than 2,000 lawsuits brought against it for overdoses caused by OxyContin. The company filed for bankruptcy in September in a bid to help it pay out in the gigantic court battle. OxyContin is a prescription painkiller produced and sold by Purdue Pharma. The drug is strong, addictive and was linked to thousands of overdose deaths in 2017. Since OxyContin, a time-released opioid, was introduced in 1996, addiction and overdoses have surged. In both 2017 and 2018, opioids were involved in more than 47,000 deaths, according to the US Centers for Disease Control and Prevention. In 1999, by comparison, there were fewer than 4,000 opioid overdose deaths. Purdue's drugs are just a slice of the opioids prescribed, but critics assign a lot of the blame to the company because it developed both the drug and an aggressive marketing strategy. According to a lawsuit filed by the Massachusetts attorney general, the company pushed big sales of OxyContin from the start. Doing so meant persuading doctors who had been reluctant to prescribe such strong painkillers that this one was safe. Some involved in the court cases are not happy about the family trying to pay out and settle before a trial because it could mean Purdue escapes liability. In a statement in September, the Sackler family said: 'Like families across America, we have deep compassion for the victims of the opioid crisis. They said their $12bn (£9bn) settlement would be an 'historic step towards providing critical resources that address a tragic public health situation.' Advertisement

The drug has been available for a long time as an injection and is astonishingly cheap – a UN program in Asia is providing it for just $1 (75p) per kit.

But the company says the nasal spray means bystanders could give it if they saw someone overdose.

When people overdose on an opioid such as oxycodone (the generic name of OxyContin) they may pass out and become unable to breathe.

Overdoses involving prescription opioids like OxyContin have soared in the past 20 years.

There were 17,029 recorded by the US Centers for Disease Control and Prevention in 2017, a 395 per cent rise from 3,442 in 1999.

And the Sacklers' Purdue Pharma is facing around 2,600 lawsuits implicating its OxyContin in drug users' deaths.

It applied for bankruptcy status in September after approaching a settlement worth $12billion (£9bn) with local governments across the US.

The nasal drug is cheaper than other ones like it, but experts are unhappy that the Sacklers are profiting from it.

Nyxoid is already being used in Australia, Norway, Sweden and addiction charities in the UK.

The New Zealand Drug Foundation's executive director, Ross Bell, said: 'The way that they’ve pushed their opioids initially and now coming up with the expensive kind of antidote – it’s something that just strikes me as deeply, deeply cynical.

'You’ve got families devastated by this, and a company who sees dollar signs flashing.'

There have been reports of internal plans at Purdue to corner the market by effectively selling both the poison and the antidote for addicts.

But Purdue and Mundipharma deny working together on the issue.

Mundipharma's Australian arm, which is selling Nyxoid to the government there, told AP: 'Mundipharma Australia and Purdue Pharma are independent companies.

'Mundipharma Australia introduced Nyxoid to help meet a clear clinical need.'

A spokesperson for Mundipharma in Europe said told MailOnline the company makes no profit from selling Nyxoid and actually sells it for around $30 (£23) a time.

They said: 'In Europe, the Mundipharma network of independent associated companies has invested over €20m into the research and development of a life-saving, alternative route of administration for naloxone and provided the product at cost price - generating no profit from its sale.

'Mundipharma developed an innovative intranasal alternative for the treatment of overdose, including illicit drugs such as heroin – a leading cause of overdose death, which has been welcomed by European health systems.

'Purdue Pharma has not been involved at any stage. Mundipharma has clinically and technically developed Nyxoid with the goal of contributing to addressing the issue of opioid overdose, in particular driven by the use of illegal heroin.'

MailOnline contacted Purdue Pharma for comment.

Mundipharma International headquarters are pictured at Cambridge Science Park in England