Heat Safety in Arizona: Knowing the Line Between Hot and Dangerous

Everyone in the Valley knows summer is hot. What is harder to know is the moment hot becomes a medical problem — and that moment arrives earlier in children, in adults over 65, and in anyone on certain common medications.

This is the page to read before June, not during it.

Call 911 now if you see any of these

Heat stroke is a medical emergency. Do not drive to a clinic, and do not wait to see if it improves:

• Confusion, slurred speech, or stumbling — the clearest warning sign, and the one people dismiss
• Skin that is hot and dry, with sweating stopped in someone who was sweating
• A temperature at or above 104°F (40°C)
• Fainting, a seizure, or unresponsiveness
• Vomiting that will not stop, so fluids cannot stay down

While you wait: get them into shade or air conditioning, remove extra clothing, and cool them with wet cloths or a cool bath. Do not give fluids to anyone who is confused or not fully awake.

The stage before that, where you can still fix it

Heat exhaustion is the body losing the argument but not yet in danger. Caught here, it resolves with shade, fluids, and rest:

• Heavy sweating, cool and clammy skin
• Muscle cramps, usually in the legs or abdomen
• Headache, dizziness, nausea
• Feeling weak or unusually tired
• A fast, weak pulse

Move them somewhere cool, have them lie down, give water or an electrolyte drink in small sips, and loosen tight clothing. If there is no improvement in about 30 minutes, or if they cannot keep fluids down, call us — or call 911 if any of the emergency signs above appear.

Why children overheat faster than you do

This is the part most national advice skips, and it is the reason a parent needs different rules than a guidebook gives.

Children produce more heat per pound of body weight than adults, sweat less efficiently, and take longer to acclimatise. A toddler cannot reliably tell you they are overheating, and an absorbed child often will not notice. Infants under six months cannot regulate temperature well at all and should be kept out of direct heat entirely.

Practical consequences:

• A car interior reaches 120°F in minutes, even with windows cracked, even in shade. Never leave a child in a vehicle for any length of time.
• Playground equipment and car seat buckles cause contact burns. Metal and dark plastic in Phoenix sun routinely exceed 150°F. Check with your hand first.
• Pavement burns bare feet, and it burns dogs’ paws for the same reason.
• Children need fluids offered to them on a schedule. Thirst lags behind need, and a child at play will not stop to ask.

Adults who are at higher risk than they realise

• Anyone over 65, whose thirst signal and sweat response both decline
• People on diuretics, beta blockers, antihistamines, or some antidepressants — several common medications reduce the ability to sweat or to sense heat. Worth asking about at your next visit if you work outdoors.
• Anyone with heart or lung disease, diabetes, or obesity
• Outdoor workers, particularly in the first week of a heat wave, before acclimatisation
• Anyone who has had heat illness before — it recurs more readily

Staying active without stopping entirely

You do not have to give up exercise for four months:

• Move it to before 8am or after 7pm. Not “morning” — the ground stores heat all day and radiates it into the evening, so late evening is hotter at ground level than the air temperature suggests.
• Drink before you are thirsty, roughly a cup every 15–20 minutes of activity.
• Use electrolytes for anything over an hour. Water alone, in volume, can dilute sodium to the point of causing its own problems.
• Take the first week easy. Acclimatisation is real and takes about 10–14 days.
• Check the forecast for the heat index, not just temperature. Monsoon humidity changes the maths considerably — a humid 105°F is harder on the body than a dry 110°F, because sweat stops evaporating.

Sun protection, briefly, because it is a separate problem

Heat illness and sun damage are different risks that happen at the same time. Arizona has among the highest UV levels in the country, and the damage accumulates from childhood.

Broad-spectrum SPF 30 or higher, reapplied every two hours and after swimming. Sunscreen is not recommended for infants under six months — use shade and clothing instead. A hat and UV-blocking sunglasses do more than most people assume, and a rash guard beats reapplying sunscreen on a child who will not stand still.

What we can help with

If you or your child has had a heat illness, it is worth a visit — recurrence risk is higher afterwards, and it is worth reviewing medications and any underlying conditions that contributed. Before a child starts a summer sport, a sports physical is the right moment to flag heat risk specifically.

And if you are unsure right now whether what you are seeing is heat exhaustion or something worse, call us. That is a reasonable question to ask, and we would rather answer it early.

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