Ask the Doctors by Eve Glazier, M.D. and Elizabeth Ko, M.D

Heat Stroke Deaths on the Rise During Dangerously Hot Summer

Dear Doctor: My siblings and I are very frustrated that we can't get our grandparents to pay attention to those "excessive heat" warnings that get issued during a heat wave. Can you help? They don't take information coming from us grandkids seriously, but I bet they'd listen to actual doctors.

Dear Reader: You've raised an important -- and timely -- issue and we're happy to help you out. You are right to be concerned because the dangers inherent in hot weather are very real, and the potential consequences can be severe. Between 2015 and 2016, the number of people who died as the result of extreme heat more than doubled from 45 to 94. Just this year, 54 people died during a heat wave in Quebec, many of them over 65.

Here in the United States, excessive heat is generally defined as two or more days in which temperatures exceed 90 degrees, often with correspondingly high humidity. While excessive heat poses a grave health threat to all of us, it is particularly dangerous for the elderly. It's also a threat to the very young, those living in urban centers who are isolated and don't have ready access to air conditioning, and individuals doing physical labor or exercising outdoors. People living with certain diseases, such as cardiovascular and respiratory illnesses, are also at elevated risk.

When we can't stay sufficiently cool, our core temperature will rise. The result is a range of heat-related illnesses. Heat exhaustion is characterized by muscle cramping, headache, fatigue, nausea or vomiting, rapid heart rate, and dizziness or fainting. More serious is heat stroke, in which the core body temperature rises to 103 degrees or more. At this point, the body no longer sweats. Instead, the skin will be hot, red and dry. In addition to the symptoms of heat exhaustion, people with heat stroke will experience confusion and even unconsciousness. These extremes in body temperatures can lead to brain and organ damage. In severe cases, multiple organ failure leads to death.

During an extreme heat warning, you should:

-- Seek out air conditioning. If you have it at home, turn it on. If not, find an air-conditioned public space like a shopping mall, public library, community center or a city-run cooling center.

-- Avoid any strenuous activity.

-- Dress in light and loose clothing.

-- Stay hydrated, preferably with water.

-- If you have any vulnerable family members, friends or neighbors, check in on them.

-- Never ever (EVER) leave people or pets in a parked car for any period of time during an extreme heat event, even in the shade or with the windows open.

With heat waves becoming more frequent and severe, it's wise to plan ahead. Know the locations of public spaces with air conditioning. Use drapes or shades to cover windows. Store plenty of bottled water and drink it. A cool bath or shower can help maintain body temperature. And if someone you know exhibits the symptoms of heat stroke, it's a medical emergency. Call 911, then use whatever means available to cool them down until help arrives.

(Send your questions to, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)