Last summer, my family and I were vacationing in San Diego and we decided to visit the famed San Diego Zoo. It was a beautiful summer day and the sun was front and center. I was so busy enjoying the exhibits and looking after my family that I neglected to fill up my water bottle as we went through the zoo. We must have been halfway into our trip and just passed the elephants when I started to feel a little “off”. Suddenly the monkeys were looking a little fuzzy and I felt like I was going to regurgitate my lunch. I had to sit down. A humbling lift to the zoo medic office and several water bottles later and I can honestly say heat exhaustion is no joke. In fact, I was fortunate that it did not progress to something more serious – heat stroke.


heat stroke, the last stage of dehydration and heat exhaustion,  is a very serious and potentially fatal condition, that is caused by extreme body temperatures and dehydration. There are two main ways that heat stroke occurs. The first is through a steady rise of temperature over many hours or days during hot weather spikes. This is more common in vulnerable populations, such as the people older than 70 or young children, who cannot regulate their temperature as well because their nervous system is unable to respond appropriately. The second kind is through physical exertion, which generally occurs when a someone working or exercising outside in the heat rapidly dehydrates in hot temperatures. The symptoms of heat stroke in order of increasing severity include having a body temperature about 103 degrees, a pulse that is rapid and strong, shallow breathing, skin that is red, dry or damp, severe headache, fatigue, delirium, confusion, seizures, and finally unconsciousness. If you are someone you know is experiencing symptoms of heat stroke it is a medical emergency and 911 should be called immediately to prevent brain damage or even death. The CDC recommends moving the person to a cooler place and attempting to lower their body temperature by giving them cool rags, fanning them, or spraying them with cool water.  Contrary to what you may think, until medics arrive, no liquids should be given to a person who is experiencing heat stroke, as there is a risk of potential aspiration.

So, now that you are thoroughly freaked out by the possibility of heat stroke, how do you take steps prevent it? First of all, it is important to be able to understand what is happening to your body when it is dehydrated and to recognize the early symptoms of heat exhaustion.

  1. Cramping – If during hot weather you start to feel any sort of muscle cramping or aches similar to when you have the flu, that is a major red flag that you may be experiencing the first signs of heat exhaustion and heat stroke. When your body is low on electrolytes, your muscles do not have the minerals to function properly. Stop and rehydrate immediately.
  2. Headache – Because the blood vessels dilate in response to heat, your head can start to pound and ache. Take the cue and find a cool place indoors or in the shade to rest and rehydrate.
  3. Cold or Clammy Skin – Another symptom of dehydration and heat exhaustion, cold and clammy skin occurs when you are sweating so much but cannot keep your temperature down. It’s similar to having a “cold sweat” when you are ill with a fever.
  4. Fainting and Dizziness – On a hot day, our bodies compensate for the heat and regulate our temperature by sweating. However, if a person is physically active or fails to stay hydrated then this progresses to heat syncope, aka “fainting”. Dizziness and fainting occur for the same reason we get heat headaches. The blood vessels dilate in an attempt to cool down our body and the resulting dilation reduces blood flow to the brain and before you know it, you can be on the ground.
  5. Nausea and Vomiting – Most people recognize that something is off when they start to feel nauseous but may not correlate it to being in the heat. If you have these symptoms combined with any of the afore-mentioned symptoms, seek medical attention, as you may need IV fluids to replenish your system.

Thankfully, heat exhaustion can be remedied by moving to a cooler area and rehydrating the body with electrolytes and water. And, it is easily preventable by taking the following simple precautions.


  1. CHECK ON YOUR  70+ year old NEIGHBORS and Friends – During a heat wave, the very young and the very old are most at risk for life-threatening reactions to heat. Their bodies are not as adept at cooling themselves in a non-airconditioned space and they may not recognize subtle changes in their own body.
  2. During hot weather spikes, WEAR LIGHTWEIGHT, COOL CLOTHING. Wearing clothes that can breathe will help your skin stay cool and your body sweat more efficiently.
  3. WEAR SUNSCREEN and a hat. Besides being bad for your skin, a sunburn can actually contribute to dehydration and heat exhaustion symptoms because it raises your body temperature.
  4. Certain MEDICATIONS can make you more prone to dehydration and heat exhaustion. For example, antihistamines, a common over the counter drug taken to combat allergies in the spring and summer, dry up the mucous membranes and can cause your body to dehydrate faster. Talk to your doctor about your individual medications and the possible side effects they may have, especially if you engage in outdoor sports or work outside.
  5. Plan your outdoor excursions for the COOLER TIMES OF THE DAY, such as the early morning or late afternoon or evening. The hottest time of the day is generally between 10 am and 2 pm. If you. Are going to be out during the hottest part of the day, be sure to take frequent breaks in shaded, cool areas.
  6. Drink LOTS OF WATER. Dehydration begins long before symptoms ever occur. Before you are going to be out in the sun, make sure you have adequately hydrated that morning and the day before and be to bring sufficient water to stay hydrated during your trip. How much water you need will depend on your level of exertion and your own individual body weight, but a good rule of thumb is to drink at least two 8 oz. glasses an hour on a hot day. If you are exercising heavily or sweating excessively, you will need more. Bring a refillable water bottle and keep it with you throughout the day.
  7. NEVER leave anyone in a parked car, even with the windows cracked of if your vehicle is in the shade, during hot weather. Temperatures in a car can rise twenty degrees in just ten minutes.  On a hot day, temperatures can get to dangerous levels very rapidly and any living thing, from children to pets, left inside a vehicle is at risk for serious injury or death.

While Seattle summers are a little more unpredictable and warm weather is sometimes wishful thinking, it always a good idea to keep these signs and symptoms of heat exhaustion at the top of your mind. The CDC has a helpful graphic that you can print out and keep on your desk at work or on your fridge to reference whenever you need a reminder. Hopefully, you now have more tools to stay cool and keep heat exhaustion from ruining your day, like it did mine!



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