FOR the benefit of anyone who has not heard a “death rattle” before, Jason Wallace puts on a short video clip. One second a cheerful Bulgarian heroin addict is shooting up. The next he goes limp, and the sound of a chilling, throaty rasp fills the room. Mr Wallace stops the tape. As the national training officer of Scotland’s naloxone programme, he is here to show a group of ex-users—about half of whom have in the past overdosed on heroin themselves—how to save the life of anyone they hear making that dreadful noise.

Not all overdoses are fatal. But the death rattle, which signals the collapse of the respiratory system, is bad news: if oxygen does not reach the vital organs in short order, the body will die. This is where naloxone comes in. When injected, it blocks heroin’s access to opioid receptors in the brain, allowing a user’s lungs to kick back into action. You hear a gasp “like a baby’s first breath”, says Mr Wallace. At the end of the session, in the Gorbals district of Glasgow, bright yellow naloxone packs, small enough to fit into a pocket, are handed out.

Spiralling drug deaths load his message with urgency. Figures for England and Wales released on September 9th showed that annual fatalities involving heroin have doubled in the past three years, to 1,201, the highest since comparable records began in 1993. Some blame the end of a “heroin drought”, which coincided with the departure of British troops from the Afghan province of Helmand and its poppy farms. Purity has risen and the price of a gram has dropped, from £74 ($100) in 2011 to £45 in 2014. Others suggest that the “Trainspotting” generation of users, who started to inject in the late 1980s, are becoming more frail.

Naloxone has been used by medical professionals for more than 40 years. But the attempt to make it more widely available—distributing it in hostels for the homeless and to heroin users themselves—is just beginning. Activists underline the potential. “Nobody needs to die from a heroin overdose,” says Judith Yates, a former doctor in Birmingham. So long as an overdose is witnessed (and 80% are), a jab of naloxone in the thigh will revive those in even the most perilous of “nods”, as the state of being very high is known. A trial in Scotland on recently released prisoners reported a 36% decline in fatalities.

Since last October drug-treatment staff in England who are not medically trained have been allowed to hand out naloxone kits themselves to anyone, including children, who they think might run into an overdose situation. The number of packs circulating has almost doubled as a result.

But provision is patchy. Unlike Scotland and Wales, England has no national naloxone programme. Local authorities have controlled their own health budgets since 2013 and roughly one-third spend nothing on the drug. Addicts in Liverpool and Leeds, to name two heroin hotspots, rely on pot luck if they overdose. During summer last year, six heroin users died in Nottinghamshire; had they lived within the city of Nottingham they would have had access to naloxone. “It’s a postcode lottery,” says Mr Wallace, comparing support in England with the system he co-ordinates over the border in Scotland.

It is not hard to see why local health-commissioners might drag their heels. Heroin users are an unpopular group. Nor will naloxone necessarily do much to persuade them to change their ways: those injected with it sometimes score in the hours after they have been “brought back”. Some areas may lack a local advocate to pester bureaucrats until they cough up for the drug.

Health budgets are strained. But that is all the more reason for shelling out for naloxone. A pack costs about £15. A 2013 study found that one would have to cost over £1,825 before it stopped being cost-effective, given the savings it generates in police work, autopsies and other things.

Australia, Norway and Sweden licensed over-the-counter sales of naloxone earlier this year. Britain should follow suit, reckons Kevin Jaffray, a former addict who was saved five times by the drug in his using days. “I wouldn’t be here without it,” he says. “From the moment of my last injection, I changed the direction of my life.” It would be cheap and easy to give thousands more like him another chance.