The Cook County Jail — the largest single-site jail in the country — has trained about 900 inmates to use naloxone nasal spray devices since last summer and has distributed 400 of them to at-risk men and women as they got out.

And Los Angeles is poised to follow suit, putting the antidote in as many hands as possible as part of a multifaceted approach to combating the nation’s opioid epidemic.

The devices can undo the effects of an opiate overdose almost immediately. They are identical to those used by officers in many of the country’s law enforcement agencies.

Sheriff Tom Dart said addicts are most at-risk of fatally overdosing in the two weeks after getting out of jail because of their time away from drugs while locked up.

Cook County Sheriff Tom Dart,

Cook County Sheriff Tom Dart. | Sun-Times files

“We’ve got to keep them alive,” Dart said. “If we can get them through that two-week window, they might get treatment, get off drugs.”

Dr. Connie Mennella, the head of correctional health for the Cook County Health and Hospitals System, which administers the program, said only inmates are being trained to use naloxone. But Mennella hopes that eventually their relatives and friends also can be trained.

“We are trying to saturate this community with this drug, and we are educating them to tell their buddy, mother, father how to use it, where they keep it and, ‘If you come home and see me not responding, to go get it and use it,’ ” Mennella said.

Proponents say such jail programs can make a life-saving difference. The naloxone often can be administered by an overdosing addict, a friend or family member before emergency responders can reach them.

Dr. Arastou Aminzadeh, correctional health-medical director for the Los Angeles County Department of Health Services, said the kits are particularly important for just-released inmates because the same amount of drugs they used to get high before being locked up could now kill them.

“Their threshold has dropped, but they may use the amount of drugs they used to use,” said Aminzadeh, who is helping the Los Angeles jail system prepare to begin its naloxone program early next year.

It’s too soon to gauge the effectiveness of Cook County’s program, but Dart said anecdotal evidence suggests the kits have saved lives, including that of a man who was arrested again, returned to jail and spoke of how a friend he trained to use the kit had done so when he overdosed.

In New York City, more than 4,000 kits have been distributed to friends and relatives of inmates at the city’s jail at Rikers Island since the program there was launched in 2014.

“We did a survey of their use of the kits after six months, and 226 people responded to the survey and found 50 usages [of naloxone] and found that 87 percent of the overdoses where the naloxone was used, [the victim] survived,” said Dr. Ross MacDonald, who heads correctional health services for New York City Health and Hospitals.

In Rhode Island, a study of 100 inmates found they were able to successfully administer the drug after being released, with a few using it to reverse their own overdoses. A study in Scotland found that the number of opioid-related inmate deaths dropped within the first four weeks of release after naloxone kits were distributed.

The growing consensus is that naloxone works. Three years ago, the World Health Organization released guidelines recommending expanded naloxone access to people likely to witness an overdose, including drug users. And the North Carolina Harm Reduction Coalition, which tracked the use of naloxone kits by law enforcement, reported the number of agencies that equip officers with kits climbed from 971 to 1,217 in about eight months last year.

There has been little pushback against efforts to expand the availability and use of naloxone, but there has been some. Richard Jones, the sheriff of Butler County, Ohio, said he’s sticking by his longstanding policy of refusing to allow deputies to carry the drug because he says people can become hostile and violent after being revived by it. Naloxone can cause severe opioid withdrawal symptoms.

Dart dismisses criticism that he’s coddling inmates by giving them the kits, saying that it’s one piece of a public health effort that includes intense treatment programs to combat the opioid epidemic.

“Treatment is fine, but that doesn’t recognize the reality that some will use [drugs] again,” Dart said. “We can’t get them into treatment if they’re dead.”