In Phoenix, Meth Doesn't Cause Heatstroke — It Hides It. That's Why July Is the Deadliest Month.

Phoenix Fire Captain Mike Johnson’s crews run this call the same way every July: someone down in a parking lot or a wash, sun still hammering at 7 p.m., dash thermometer reading past 114. The person isn’t sweating. Their skin is hot and dry. They’re agitated, talking fast, not making sense — and the first read from a bystander is always the same word: overdose. Sometimes it is. Sometimes it’s heatstroke wearing an overdose’s clothes, and by the time anyone figures out which, the person is unconscious on pavement hot enough to burn skin on contact.

That confusion is not a bystander’s failure. It’s the point. Meth raises your core temperature and disables the two things your body uses to tell you it’s overheating — sweating and thirst — at the exact moment a Phoenix summer needs both working at full capacity.

Methamphetamine doesn’t just get more dangerous in a Phoenix summer — it converts the body’s own warning system into a liability, and Maricopa County’s own mortality data proves it’s killing people who have no idea what’s happening to them until they’re already down.

This isn’t a seasonal quirk the county is still puzzling over. It’s a pattern with a decade of receipts, a known mechanism, and a policy response that, as of this year, is moving in the wrong direction.

July Kills at More Than Double January’s Rate, and the County Knows Exactly Why

Maricopa County’s fatal overdose numbers don’t drift upward gradually as the mercury climbs. They spike, hard, every July. Between 2022 and 2024, fatal overdoses in July ran more than twice as high as they did in January — the same population, the same drug supply, the same city, and still, a monthly death toll that doubles the moment the heat arrives. The county’s worst single stretch on record was July 2023, its hottest month ever measured, and it produced the highest fatal overdose rate the county has logged.

The county’s own heat surveillance data backs this up from the other direction. In 2025, Maricopa County confirmed 430 heat-related deaths. Substances were involved in 55% of them — 236 people who died from the combination of heat and drugs or alcohol, and nearly all of those 236 involved stimulants, not opioids. Opioids showed up in less than 47% of the substance-involved heat deaths. Meth was the dominant driver. Zoom out to the county’s full overdose picture and the same drug keeps showing up: 67% of the county’s fatal overdoses involved methamphetamine in 2024, against 59% for fentanyl — categories that overlap constantly, because most of what kills people in Maricopa County now is polysubstance, not one drug acting alone.

Put those numbers next to each other and the story isn’t “overdoses go up in summer.” It’s that a specific, identifiable drug class turns a survivable Phoenix afternoon into a fatal one, and the county has been documenting exactly how for years. This is not a mystery anyone in Arizona’s overdose-response infrastructure is still working out. It’s a known seasonal kill pattern that keeps recurring because the information isn’t reaching the people who need it before they’re the ones on the pavement.

Your Body Has One Cooling System. Meth Breaks It.

Here’s the mechanism, in plain terms, because understanding it is the difference between recognizing an emergency and waiting it out.

Your body cools itself two ways: it sweats, and it moves blood to your skin so heat can radiate off. Meth interferes with both. It’s a stimulant, which means it speeds up your heart rate and narrows your blood vessels — a process called vasoconstriction, which just means your blood vessels are squeezing tighter and carrying less blood out to your skin’s surface, where it would normally shed heat. Less blood at the surface means less cooling, even as your body is generating more internal heat from the drug itself and from the exertion that often comes with using it.

Ariella Dale, chief science officer at the Maricopa County Department of Public Health, lays out the chain plainly: stimulants “make us more dehydrated, it’s harder to regulate your temperature, it increases your heart rate.” That combination, she says, “intensifies the effects that we already think about when thinking about heat-related illnesses and death.” Dehydration on its own is dangerous in a Phoenix July. Dehydration plus a drug that’s actively working against your body’s temperature regulation is a different category of risk entirely, and it’s why stimulants were involved in 8 out of every 10 heat-related deaths that involved substance use in the county’s data.

The cruelest part is what meth does to your ability to notice any of this is happening. Captain Johnson has watched it play out on scene after scene: “It can really kind of mask symptoms that they’re having. They might not be realizing that they are not sweating anymore or that they’re thirsty,” he told AZFamily. Stimulants blunt the warning signals your body would otherwise be screaming at you — the dry mouth, the stopped sweating, the dizziness — right when you most need to catch them. “Stimulants also really increase the internal temperature of your body,” Johnson said, and once that internal temperature crosses a threshold, the clock moves fast: “Heat stroke is definitely a life-threatening emergency and it happens very quickly, especially once you start getting into that altered state.” Collapse outdoors in July and the danger compounds again — pavement and asphalt in direct sun can exceed 150 degrees. “If you were to pass out in this heat, you’re not only looking at heat exhaustion, now you can be talking about burn injuries,” Johnson said.

They might not be realizing that they are not sweating anymore or that they’re thirsty,” he told AZFamily.

If You’re Using Outside This Week, Here’s What Actually Keeps You Alive Tonight

If you’re using stimulants outdoors in Phoenix right now, your body is already working overtime just to survive the heat — meth adds a second full-time job on top of it, and it’s the job that doesn’t clock out when you tell it to.

A few things matter more than they might seem to in the moment. First: carry naloxone, even though you’re using meth and not opioids. The meth and pill supply in this region is contaminated with fentanyl often enough that Dale’s own advice to the public is explicit: “we’re just trying to share with our public to consider, when they’re using these substances, that they have naloxone on-hand to prevent any kind of fentanyl or opioid-overdose incidents.” Naloxone won’t touch the heatstroke risk, but it can save you or the person next to you from the opioid contamination layered on top of it — which is exactly the kind of stacked risk this newsroom has tracked as naloxone access has struggled to keep pace with demand statewide.

Second: don’t wait for thirst to tell you to drink water — it may not. Hydrate before and during, not just after, and don’t assume feeling okay means your body is regulating its temperature normally.

Third, and this is the one that actually changes outcomes: if you or someone with you gets confused, agitated, stops sweating, or has hot dry skin, treat it as heatstroke, not “a bad high” you ride out. That’s a medical emergency that kills fast, and the fix isn’t more time — it’s shade, water, and getting cooled down immediately, ideally with EMS on the way. Arizona’s Good Samaritan law, A.R.S. 13-3423, protects both the person overdosing and the person who calls for help from prosecution for drug possession when the evidence comes from that 911 call — it doesn’t erase every legal risk, but it exists specifically so fear of a possession charge doesn’t stop someone from picking up the phone. And don’t use alone outdoors in the middle of the day if you can help it at all. Midday sun in a Maricopa County July isn’t a backdrop — it’s an active participant in what kills you, and there’s no version of using stimulants alone in it that isn’t higher-risk than using around someone who can notice when you stop making sense.

Arizona Has Been Here Before — It Just Called It Something Else

Addiction researcher Daniel Ciccarone named this the “fourth wave” of the overdose crisis: after prescription opioids, then heroin, then fentanyl, the current wave is stimulants showing up contaminated with or alongside fentanyl. Arizona lived an earlier stimulant wave and mostly answered it with handcuffs. Phoenix meth-related deaths tripled between 1997 and 2001, from 34 to 122, and the Justice Department ranked Phoenix first among 33 metro areas for meth-related emergency room visits by 2001. The state’s response then was lab raids and mandatory minimums, not naloxone kits or hydration stations — because that infrastructure didn’t exist yet. It took the opioid era, and thousands more deaths, to build the tools a stimulant crisis is now borrowing to survive.

Phoenix Just Restricted the People Doing This Work, in the Deadliest Month of the Year

This is where the county’s data and the county’s politics stop lining up. Sonoran Prevention Works, a Phoenix harm reduction organization founded by and for people who use drugs, has spent years running street outreach in city parks — naloxone kits, hydration supplies, the unglamorous work of finding people before heat and drugs find them first. A new Phoenix ordinance now restricts groups from providing medical care or distributing harm reduction supplies in city parks without city authorization, and it lands during the exact month the county’s own data says is most dangerous.

Scott Greenwood, Sonoran Prevention Works’ CEO, doesn’t mince the consequence: “There will be fewer calls for service for people reporting activity that they find distasteful in the parks, and more reports that require EMT or ambulance runs to people who have overdosed because they did not receive the services,” he told KJZZ. “And unfortunately, more people dying.” His organization’s outreach kits carry exactly the tools this article is telling you to have on hand — naloxone with instructions, electrolytes, basic supplies to manage the physical toll of using in extreme conditions. Pushing that outreach out of the parks where people who use drugs actually are doesn’t make the July spike smaller. It just moves the response further from the people who need it, in the month the county’s own mortality reports say they need it most.

It just moves the response further from the people who need it, in the month the county’s own mortality reports say they need it most.

Take a position on this and it isn’t a hard one: a city that has the data proving July is a body-count month for people who use stimulants outdoors should be expanding outreach into its parks right now, not restricting who’s allowed to hand out naloxone in them.

What’s Still Real Tonight

None of this changes because a city ordinance made outreach harder. Naloxone is still free and still works on the fentanyl that’s turning up in this region’s meth and pill supply — Sonoran Prevention Works still distributes it, ordinance or not. The Heat Relief Network — more than 200 cooling centers, respite sites, and hydration stations across the Valley — runs free through September 30, and calling 211 will route you to the nearest one, no questions asked about what you’re on when you get there. None of that requires you to be sober, housed, or anything other than alive and looking for shade.

Captain Johnson’s crews will still run that call this week — someone down, sun still up, skin hot and dry. What changes the ending isn’t the heat and it isn’t the drug. It’s whether the person next to them, or the person themselves an hour earlier, knew that a body that’s stopped sweating in 115-degree heat isn’t riding out a high. It’s running out of time.