Most of us don’t love the heat. Even if you enjoy hotter weather, an unrelenting heatwave can be one of the worst parts of summer.
You cannot hang out in a swimming pool or sit in front of an air conditioner all day, so facing the heat is part of life in most areas of the world. However, some people have a much harder time dealing with heat than others.
If you or someone you love experiences drastic reactions to heat or high humidity, you may have heat intolerance.
Understand What Heat Intolerance Is and Why You Might Have It
You can be heat intolerant because of a variety of health conditions or factors.
Being overweight can cause difficulty in dealing with heat, as can being elderly. Infants and young children are less able to cope with heat than older children and adults, and those with endocrine or neurological disorders or sensory processing issues are more likely to be heat intolerant than those without these concerns.
High or low blood sugar can lead to less tolerance for heat. If you have recently eaten a high-card or high-sugar meal or are already feeling hungry or weak, your tolerance for heat is likely to be reduced.
There are many other medical conditions that might cause heat intolerance, too. Multiple sclerosis is one of the most common. People with MS can experience multiple symptoms of heat intolerance even in relatively mild temperatures.
Many people who experience symptoms of heat intolerance are also dealing with a condition known as dysautonomia. This condition is one in which the autonomic nervous system is impaired, impacting the body’s reaction to common stimuli including movement and temperature changes.
What causes dysautonomia? It can be an effect of a variety of conditions, including diabetes, Parkinson’s Disease, and even alcohol abuse. There are also at least fifteen different variations of dysautonomia, including
- Neurocardiogenic syncope
- Postural orthostatic tachycardia syndrome (POTS)
- Diabetic autonomic neuropathy
- Multiple system atrophy (MSA)
There are also types of dysautonomia that stem from spinal cord injuries, failure of the baroreflex system, and even genetic predisposition. Regardless of what type of dysautonomia a person has, it is sometimes the root cause of recurrent heat intolerance and its symptoms.
Other reasons that a person might be experiencing heat intolerance include certain allergies, issues with blood pressure, and medications. Decongestant medications are some of the most common culprits of causing heat intolerance, but almost any medication could potentially do so in higher doses or in the first days of use.
With so many ways to trigger this problem, it is no wonder so many people suffer from symptoms of heat intolerance every summer. But what exactly is heat intolerance – and how is it different from normal reactions to heat and humidity?
The difference is all down to severity and the body’s inability to stabilize itself while suffering from the symptoms.
Signs and Symptoms of Heat Intolerance
It is normal to sweat in high temperatures. Feeling uncomfortable outdoors on humid, muggy days is also normal. Even a person without heat intolerance will experience exhaustion if they stay in a hot environment long enough.
So, what makes heat intolerance different from normal reactions to heat? Generally, the symptoms of heat intolerance happen much more quickly and severely than normal heat reactions. What might take hours for a normal person to experience may take as little as a few minutes for a person who is heat intolerant.
Some of the most common symptoms experienced by people with heat intolerance include:
- Feeling very hot when others do not, including in moderately warm temperatures.
- Mood shifts or cognitive changes.
- Itching, patchy, or hive-like rash.
- Racing heartbeat or pulse.
- Redness of the skin that resembles – but is not – sunburn.
- Nausea or vomiting.
- Dizziness, feeling lightheaded, or even passing out.
- Headaches or vision disturbances.
- Exhaustion or fatigue.
- Muscle cramps or soreness.
- Excessive sweating.
- Not enough sweating. (This is actually more dangerous than excessive sweating because it can be an indication of dehydration.)
- Triggered symptoms of chronic health conditions such as migraine or epileptic seizures.
Individual responses to heat by heat intolerant individuals will vary. However, even those that seem harmless – like feeling tired or irritable due to heat – can be signs of greater issues such as heat exhaustion or dehydration. Heat exhaustion can lead to heatstroke if you do not address it promptly – and heatstroke can be fatal.
Coping with Heat Intolerance and Preventing Symptoms
How can you survive summer with heat intolerance?
The truth is, there is no simple answer. What works for some people who suffer from heat intolerance might not work for others. A good idea is to use trial and error to find the method or combination thereof that works for you or your loved one.
Some approaches to preventing symptoms include:
- Maintain a healthy body weight and an adequate activity level. While this will not prevent immediate problems with heat, it will help to condition your body to better handle heat in the future.
- Eat properly and regularly. As mentioned previously, blood sugar levels can impact your tolerance for heat.
- Don’t drink too much caffeine. Stimulants like caffeine can make you much more susceptible to high temperatures and reactions to them.
- Stay hydrated. Hydration is always important, but especially when you are trying to prevent heat intolerance symptoms.
- Avoid strenuous activity, especially when you are in a hot or humid environment.
- Use air conditioning or fans when possible.
- Avoid alcohol and drug use. Substances that impair your judgment and your body’s normal processing will also impair your ability to cope with high temperatures.
You may need to talk to your medical provider about changing your medication if you feel that it is causing your heat intolerance or making it worse. Likewise, you may consider asking them if they can suggest an additional medication that will offset that concern.
The best way to prevent heat exhaustion and other symptoms of heat intolerance is to stay in temperature-controlled environments and to dress minimally when you are in higher temperatures. Breezy, breathable fabrics and lighter-colored clothing will help your body better regulate its temperature.
If you know that you will be outdoors, it is also best to avoid direct sunlight. In most places, this means avoiding time outdoors between 10am-2pm, although warmer areas that get more sunlight may require avoiding sunlight until 4pm or later.
If you know that you will not be able to avoid a hot environment, consider the following measures to counter the symptoms of heat intolerance:
- Cool down. Ideally, this means moving into an air conditioned area, but if that is not possible, move into the shade until you are able to find a cooler environment.
- Lower your body temperature. If you are experiencing symptoms of heat exhaustion, you likely have an elevated body temperature. Lower it by consuming cold food and drinks or try a cold compress on the back of your neck.
- Sit in cool water. A shallow swimming pool or bathtub filled with cool water can also help you lower your body temperature safely. Just don’t make the water ice cold, or you can send yourself into shock. (Also be sure to have someone monitor you or your loved one in a pool in case you lose consciousness.)
- Lie down. If you are dizzy, tired, or experiencing other common heat-related symptoms, you might feel better after lying down.
- Rest your head. If you cannot lie down, lay your head down until symptoms begin to subside.
As you can see, the general rule of thumb is to get yourself or the person who is experiencing symptoms out of the hot or humid environment as quickly as possible and relax until those symptoms pass.
Relieving Heat Intolerance Symptoms
Life happens. Remaining in a cool, comfortable environment is not always possible or practical. When that is the case, experiencing heat intolerance symptoms may not be avoidable either.
So, what can you do if you have already been stricken by these symptoms? Thankfully, heat intolerance is generally not dangerous if addressed promptly – and symptoms typically subside within hours or even minutes.
As mentioned previously, the best way to address symptoms in a heat intolerant person is to remove them from the triggering environment. If you are the person experiencing symptoms and you have to drive, try to sit in a cool car for a few minutes before doing so.
If you have someone else with you who can, ask them to drive you home or to a safer location.
Once you are in a safer location, be sure to hydrate. Even if you did not sweat profusely during your experience, your body will benefit from hydration – and you will likely feel better, faster.
If your symptoms are severe, your best bet is always to call an ambulance or have someone take you to the emergency room. While you may not think that something that happens to you regularly is enough of a concern to merit a trip to the hospital, it is always better to err on the side of caution.
What counts as severe? If you or your loved one experiences any of the following, seek medical attention right away:
- Body temperature of 103 or higher.
- Cessation of sweating or inability to sweat.
- Difficulty swallowing.
- Trouble breathing.
- Confusion or slurred speech.
- Loss of consciousness, even for a short time.
At the hospital, you will likely have your vitals taken and be checked for other issues involving your heart and breathing. During this time, you will probably also be given IV fluids to ensure that you are not dehydrated.
Be sure to tell your medical provider what environment you were in and activities you were doing when symptoms began, as well as what those symptoms were. This disclosure will help them determine the best course of treatment for you and deliver it promptly.
Regardless of where you are treated for your heat intolerant episode, be sure to keep track of when and why it likely happened. Identifying your triggers can help you avoid future issues with heat.
Are you heat intolerant? Is someone you love coping with heat intolerance this summer or have they suffered from these symptoms previously? As summer continues, be sure to remain vigilant for potential risks and keep one another hydrated, healthy, and safe!