8 Things to Know About Drinking in Summer Heat and Hot Weather

Note: While research on alcohol is evolving, the Centers for Disease Control and Prevention says drinking less or not at all is better for your health.

Drinking alcohol on a hot summer day can increase your risk of heat sensitivity and dehydration. It can also introduce unique dangers, such as the risk of extreme sunburn (if you’re squeezing citrus for mixed drinks).

Awareness of these risks can help you take proper precautions to stay safe in the summer heat and still enjoy your favorite drinks responsibly.

1. Alcohol Is a Natural Diuretic (and Can Raise Dehydration Risk)

Because it's a diuretic, alcohol increases the amount of fluid you lose through urine.

2. Heatstroke and Intoxication Look Similar

“Heatstroke and alcohol intoxication can look similar,” Thankachen says. “That is dangerous because people may assume someone is ‘just drunk,’ when they may need urgent medical care.”

3. Alcohol Interferes With Your Internal Thermostat

“Alcohol dilates your blood vessels, so you feel sort of warmer than you are, then drinking further dehydrates you on top of the heat,” says Miriam Fischer, MD, an emergency physician at MedStar Health based in Washington, DC.

It’s important to listen to your body carefully so you can notice symptoms, which is harder if you’ve had too much to drink, Dr. Fischer adds. “If you start feeling symptoms of heat exhaustion, like getting lightheaded, dizzy, getting a headache, or starting to feel nauseous, you’ve got to get yourself out of the heat.”

Every summer, Fischer says her emergency department sees multiple patients who have had too much alcohol and passed out outside in the heat because they didn’t realize how hot they were getting. In these situations, people can start with heat exhaustion and then progress to heatstroke or die of the heat.

4. Sugar Also Dehydrates

“Sugar pulls water into the gut and can increase fluid loss, which can also lead to quick spikes and drops in blood sugar,” Thankachen says. “Those swings often feel like energy crashes, irritability, and lightheadedness.”

In hot weather, these effects can feel more intense because the body is already under stress, Thankachen adds.

5. The ‘1-to-1’ Rule Is Nonnegotiable

“In summer heat, many people need more than that to stay hydrated,” Thankachen says. “Sweat loss can vary by person, activity, and humidity.”

As a practical approach, Thankachen recommends drinking extra water, taking breaks in the shade, and watching for early dehydration signs like dry mouth or dark urine. Dehydration can also have unusual symptoms, including bad breath, muscle cramps, and food cravings.

6. Beware of ‘Margarita Burns’

“Phytophotodermatitis often shows up as streaky, blistering, or hyperpigmented patches on the skin,” says Melanie Palm, MD, a board-certified dermatologist and cosmetic surgeon at Art of Skin, MD, in Solana Beach, California. “Washing your hands thoroughly with soap and water helps remove those compounds before they have a chance to react with sunlight.”

When you’re drinking outside, it’s also crucial to remember to reapply sunscreen regularly. “It's easy to lose track of how hot it is and how bright the sun is, especially if you are drinking, and we also see lots of sunburns,” Fischer says. “Remember to put on that sunscreen before you go out, and consider a hat."

7. Medications Can Amplify the Risk

“Adding alcohol can worsen dizziness, sedation, dehydration, low blood pressure, low blood sugar, and poor judgment,” Thankachen says. “Read medication labels and ask a clinician before mixing alcohol with prescriptions.”

Even if your doctor says you can have some alcohol with your medication, still monitor closely for signs of dehydration.

“Certain blood pressure medicines called diuretics make you go to the bathroom, antihistamines increase your risk of dehydration, and then drinking does both,” Fischer says. “Heat adds to that risk, so I would strongly recommend limiting your alcohol intake, limiting your time in the heat, and most of all making sure that you’re drinking as much water as alcohol.”

8. Drink Carefully if You Have Certain Conditions

Chronic conditions can change how alcohol affects the body in hot conditions. Heart disease, kidney disease, liver disease, diabetes, high blood pressure, and seizure disorders can increase your risks, Thankachen says.

“In many cases, heat, alcohol, and dehydration can make symptoms less predictable,” Thankachen adds. “People with chronic conditions should be more cautious, drink less or not at all, and seek medical guidance if they are unsure.”

The Takeaway

• Alcohol can affect how your body processes fluids and regulates heat, and ingredients such as sugar and caffeinated mixers can increase its dehydrating effects — making drinking and hot summer days a potentially dangerous combination.
• Certain medications and underlying conditions can amplify heat sensitivity, while handling certain ingredients in drinks like citrus fruits can put you at risk of extreme sunburn.
• Always follow the “1-to-1” rule: Drink one full glass of water for every alcoholic beverage you consume.
• Because heatstroke and alcohol produce similar symptoms, it’s important to stay well hydrated, monitor symptoms closely, and call 911 if you or someone you know might be experiencing heatstroke.