ask: Why does even 5 minutes of sun cause headache - and 10 mins cause nausea?

The body has a natural cooling mechanism. But, if too much body fluid is lost through sweating, the body overheats. But, this may just be heat exhaustion. It's important to stay hydrated, and this is something I'm particularly aware of because I'm in marathon training in the heat of summer - yikes!

There was a comment during today's broadcast of the Tour de France about how the cyclists must be constantly hydrated on their hard climb into today's mountain stage, not only because of the heat but because of the amount of body fluid they lose to their exertion. Hydration helps the body's natural cooling mechanism. While we're not exerting ourselves to quite the same level, the heat can still take a toll on us if our bodies are not properly hydrated.

When the brain is affected by elevated body heat, the condition becomes dangerous. This is a heat stroke symptom.

Understanding Heat Related Symptoms

Heat Exhaustion and Heat Stroke Symptoms

Extreme heat A Deadly Risk for Older Adults

His symptoms happen so quickly that it can't be lack of hydration unless he is generally dehydrated - I will ask him about his liquid intake while at work all day.

He said he did read somewhere that some people are very sun sensitive and show these symptoms within minutes but he's honestly the only person I know who is reduced to headaches and throwing up within minutes. Talk about super sensitive!

Thanks for your reply and the links -

I'm happy to find this here but sad theres no response because I have the same 'thing' as your husband.

I can only handle about 20 minutes in direct sunlight before I get a migraine like headache and start throwing up. The vomiting doesn't stop until I've passed out from exhaustion, then once I wake up I'm fine but this generally takes 8-24 hours.

You're right that it's not dehydration because it happens so quickly and I drink a lot of water anyway. It seriously feels like my brain is cooking in my skull but my body temp doesn't rocket and I'm not covered in sweat. It's all head related.

I'll keep an eye on this message board, hopefully someone can add some insight.

Thanks for posting!!!

Did you read through the Heat Exhaustion/Stroke symptoms article? I know, you have to click through consecutive pages, which is a bit time-consuming!

Since we're all different, we'll each have a different threshold and set of symptoms. For example, a few weeks ago, I had a 10K race in high heat and humidity. I knew I was in trouble inside mile 6 and headed straight to the medical tent after crossing the finish line and collapsed just as the medic reached for my arm. I was promptly treated for heat stroke.

Last Saturday, I had a mere 5 mile run, and it was about 76F/50% humidity at 6:30 a.m. About 45 minutes later, the temperature was pushing 80F, there was no cloud cover to protect us on our route, and the humidity was rising. Being in full sun all that time, I started feeling nauseated; worse, I was getting a nagging headache and felt like my head was heating up. Fortunately, my buddy and I were only a couple of blocks away from our finish.

Sunday, I had 8.5 miles to do, but there was a lovely breeze and lots of cloud cover. It was about 75F and maybe 45% humidity. We also had the advantage of two water stops along the route and long stretches of shady woods, so we could either cool off or stay relatively cool. At the finish, my buddy and I cooled off in the kid's water playscape in the park where we had our run. What was really weird is that my buddy was sweating profusely and drank about 40 ozs of water, while I wasn't sweating all that much and only went through 12 ozs of water.

The difference was in the intensity of the sun and the humidity level. Your body's cooling mechanism isn't as efficient in high humidity.

Here's an important section of that article:

page 2 - http://www.emedicinehealth.com/heat_exhaustion_and_heat_stroke/page2_em.htm

page 3 - http://www.emedicinehealth.com/heat_exhaustion_and_heat_stroke/page3_em.htm

Hope this helps.

My wife gets migrane headaches within minutes of going into bright sunshine. The often last for hours. I am curious if anyone has any ideas that might help. Someone told her chugging a bottle of Gatorade sometimes helps. It has helped her a couple of times, but not always. Maybe the person who made the suggestion is a Gatorade salesman. We are open to suggestions.

I have had these same symptoms for years. It always happens on hot summer days when I am exerting myself in the sun.
Yesterday, I helped a family member move furniture and it was around 88-F. I was able to go for around 4 hours and then the precursor to the nausea came on: a dull headache. I spent the next 2 hours throwing up with dry heaves so bad, and wretching so bad, that it broke the tiny blood vessels in my face. I spent 2 hours laying on a cold bathroom floor next to the toilet. Whenever this happens, my body breaks out in tremendous sweat and I am drenched from head to toe. After about 2 hours of laying there with a fan on me, it subsided. My body will then go into a chilling effect where I feel extremely clammy. This happens about once or twice every summer. Last year, it happened after trying to remove a tree stump in the backyard. The only thing you can do is lay down with air blowing on you and wait till it subsides.
I know that it has nothing to do with hydration as I continuously drink water during all my time in the sun. I hypothesize that it has to do with a sun allergy.
I've learned to try to control it as I only cut grass after 6 pm and stay away from doing outdoor activities during the heat of the day.
I've had this go on for as long as I can remember and the only thing I can link it to is the sun exposure. I can be inside and run 3 miles on a treadmill and sweat profusely but it won't cause my symptoms.

I have the same issue. If I go outside for more than 4 or 5 min in the sun without my sun glasses on. For me the headaches started around 13, at 18 I discovered sunglasses. Now I work outside all day everyday and don't really get too many headaches. My doctor said that it was because of my eye color, they are a very light blue, any light colored eye is susposed to put you at a higher risk. The problem with this theory is that I also get bad headaches if I'm hungry and don't eat right away, and my latest problem is the rain. It didn't bother me until about a month ago, but if it's hot outside and then all of a sudden it poors and the temp drops it's an instant migrane. So I understand your pain, 4-5 min outside and I have a headache that the only way to relieve is to go inside in a very dark room and sleep. If I'm out for 10 min I'm throwing up... still haven't found a quick fix for that. Anyways I would try sunglasses, I work at a golf course and people pick on me because of my "racoon" eyes, but I don't care because it's better than throwing up. Try "eyejacket" type of sunglasses because they block more of the light

i have the same problems.

does it happen in the winter sun? If not it could be allergies in the spring/summer. We all change as we get older.
talk to your your Doc about a Flonase prescrip. or try otc stuff first

staying hydrated, wearing sunglasses and wearing a cool ventilated hat (not a baseball cap) also help me