Jonathan Leyvas opened the lid of a dumpster on a hot July morning in Mesa, Arizona, hoping to find something useful or valuable inside.

Like many people without homes in metro Phoenix, he lives day to day. Leyvas, 32, washes cars or mows lawns for a few bucks, scrounging for something to eat and to help him buy drugs. He planned to smoke methamphetamine later, he said, adding that he believes his drug use is the reason for his homelessness.

He’s familiar with the signs of heat exhaustion — he’s experienced it many times.

“The heat, like, messes with your senses and stuff," he said. "You’ll be dizzy, like hallucinating. Mad all the time.”

Like others interviewed for this article, Leyvas had no idea that meth is much worse than fentanyl when used in hot environments.

“I don’t think it’s as dangerous as blues,” he said, using the street name for fentanyl pills derived from their distinctive color.

Scientific studies and Maricopa County’s Heat-Related Illness and Death Dashboard show this belief is inaccurate.

Meth use by itself can cause heat stroke and death even when used at room temperature. The drug wreaks havoc with the body’s heat-regulation systems and spurs motion that generates internal heat.

In metro Phoenix, America's hottest big city, where summer temperatures routinely exceed 110 degrees, amphetamines — mostly meth — were either the primary cause of death or a related cause in 51% of the record 645 heat deaths in Maricopa County last year. The county's total of 645 combines both heat-caused and heat-related deaths.

Told this, Leyvas seemed to express genuine surprise. He issued an expletive.

“So I’ve been putting my life at risk all these days?” he said.

He had a simple plan to get off the streets temporarily: He would turn himself in to police on July 30 and serve 15 days for a minor crime, he said.

“But I'm definitely not gonna be smoking meth no more and being on the heat,” he said.

“I don't want to die. Like, I already survived twice. And wouldn't want my mom to lose another son, 'cause she already lost two sons.”

Meth associated with the greatest number of local heat deaths

Substance use greatly exacerbates the summer toll of heat-associated deaths in metro Phoenix, Maricopa County Heat-Related Death Reports show.

Take away substance use and the record heat-associated deaths in Maricopa County last year would have fallen to 226, or 35% of 2023's total of 645.

But not all drugs affect the body's heat response equally.

"If there were any drug out there that makes you more prone to heat or heat-related illness, it's very hard to think of any other drug besides meth," said Dr. Frank LoVecchio, an emergency physician, noted researcher and expert on medical toxicology and heat-related deaths.

Meth is also a huge factor in the increasing number in the last two years of contact burns on sidewalks and streets that can reach up to 180 degrees, a recent study of cases by Valleywise Health shows.

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Other drugs with amphetamines — including MDMA, or drugs for ADHD like Adderall — can be a danger, too. So can drugs that cause dehydration. Even widely used medicines like Benadryl can decrease the body's tolerance to heat in part because they reduce sweating, which helps keeps the body cool, LoVecchio said. Yet if someone came into an emergency room because they took Allegra, an antihistamine, he said doctors would view that as "rare."

Unsheltered people bear twice as the risk as sheltered drug users. But even among people who have homes, meth-related or meth-caused heat deaths were nearly twice as high as for fentanyl, the county's 2023 heat-death report shows.

A 2020 review by the Centers for Disease Control and Prevention shows people who work outside and use meth or other amphetamines are also at severe risk of dying. Medical conditions like cardiovascular disease or diabetes are also believed to increase the chances someone on meth will die from a heat illness.

The problem of meth and heat has received more attention from the news media in the last two years, and the county has published some information about it. But Maricopa County hasn't produced and aired any public service announcements about how dangerous meth can be in the heat.

The county's main website about heat illness and "heat toolkit" site doesn't mention the issue on their homepages, and the site's page about preventing heat-related problems tells readers to avoid "liquids with large amounts of sugar, alcohol or caffeine products" and that "using substances" can put people at risk, but doesn't tell people to specifically avoid meth or amphetamines.

LoVecchio said meth use in the heat should be "strongly discouraged."

"You want to scream it to the top of the mountains," he said.

Yet many homeless people don't seem to be getting the message.

'Shocked' that meth is more dangerous

In the courtyard at the Mesa St. Vincent De Paul shelter the same day Leyvas said he would quit meth, a group of people told The Arizona Republic, part of the USA TODAY Network, they had not heard meth was more problematic in the heat than "blues."

A few days later, on an afternoon when the temperature was 106 degrees near Andre House in Phoenix, The Republic found a similar response from unsheltered people.

"I don't believe it," said Lori Fay, 55, sitting on a folding chair in the sun with her two panting dogs.

Thomas Hull, 37, standing in line for Andre House's meal service, said he thought blues were the most dangerous in the heat, noting "people don't have enough water."

Carmela Colmerauer, 51, said she was staying at the nearby Central Arizona Shelter Services and was homeless for the first time. She said she was "shocked" by the news.

Colmerauer and several others said they knew fentanyl, a synthetic opioid more powerful than heroin, could knock people out. They'd seen people unconscious in the heat, unable to take care of themselves. Colmerauer noted many drug users "mix blues and meth," which county statistics also show.

Solutions not as easy for meth as fentanyl

Meth users may experience body temperatures as high as 110 before they die. Survivors of hyperthermia, the scientific term for having a severely high body temperature, may still suffer from permanent brain damage. Treatments for hyperthermic meth users are few.

"If you come into the ER and you had a near-death experience with opiates, we'll give you things like Narcan," LoVecchio said. "There's no antidote for meth."

While no randomized tests can be performed on humans with meth, it's clear from experience that someone suffering from heat illness will respond better to treatment if they haven't used the substance, he said.

First responders or medical personnel may want to put the overheated in ice-filled "body bags" or dump ice water on them. But meth users may resist such treatment, spurred by paranoia brought on by the drug. They may try to fight with people trying to help them, which in turn raises body temperature, making the person's condition worse.

Cold environments can prevent meth-induced overheating, studies show, indicating meth addicts could consider moving to cooler climates to stay alive. Those who choose to live in the desert and use meth have few options to reduce their risk.

They can avoid exercise and movement outdoors after they consume, perhaps heading directly to a cooling center to lie down. Other studies suggest they should avoid social gatherings or becoming aroused, which exacerbate the negative effects of meth in the heat.

A 2022 study suggests health care workers could administer coral calcium hydride, "a newly identified hydrogen-rich powder" to meth users experiencing hyperthermia. The compound "inhibited meth-induced depression-like behaviors" and reduced brain damage, the study says.

Educating meth users about their elevated heat risk

The county's Public Health Department runs drug-abuse programs, and its 2023 Strategic Plan on abuse funds various initiatives "to stem the harms of fentanyl, meth and other drug use," said Fields Moseley, a Maricopa County spokesperson. Those include funding for "two dedicated navigators with lived experience at Correctional Health Services to solely engage drug users while they are detained/incarcerated," he said.

The county works with partners in the community to reach drug users and purchase electrolyte packets for street outreach distribution, he said. A brochure titled "Drug Use and Heat Don't Mix" that mentions the special danger of meth and stimulants is being distributed to drug users on the street.

Dr. Jeff Johnson, chief medical examiner in Maricopa County, often speaks about the issue, Moseley said.

Another county spokesperson, Courtney Kreuzwiesner, told The Republic the county is in the process of expanding its educational information about meth and amphetamines on its websites.

The updates "will feature more content about the groups and conditions our data identify as higher risk for heat illness and death, including people who use drugs" and "data highlights related to stimulant and other drug use as contributing factors," she said.

Representatives from Andre House and Central Arizona Shelter Services did not return requests for comment on if they provide advice on meth to those they serve.

Reach the reporter at [email protected]. Follow him on X@raystern.

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