The reason I ask is Heat Exhaustion (leading to Heat Stroke) and Hyponatremia can have very similar signs/symptoms. The difference is Heat Exhaustion patients need water; Hyponatremia patients need sodium (and, perhaps, other electrolytes). Bananas have hardly any sodium and neither does Vitamin Water (the Vitamin Water has some other electrolytes, but not sodium). The Clif bar does have some sodium, but not a great deal (maybe 6% of the "daily need" based off the 2,000 calorie diet standards - again, not a lot). It seems to me that if you had Hyponatremia the water and vitamin water intake would have worsened your condition. However, each person acts a little different when suffering Hyponatremia depending upon their level of sodium deficiency.
This was not dehydration with a history of peeing clear and no rapid fluid loss from N/V/D. Like my buddy Shaw and others have said, my first thought too was hyponatremia. Then as the story progressed, just as Emily pointed out, I was surprised that the Clif Bar and Vitamin water helped the situation. Thus I no longer think it was hyponatremia.
jimlup mentioned AMS. According to my NOLS WEMT book, S/S of AMS are Headache w/ one of the following: N/V, loss of appetite, mild lassitude or fatigue/weakness at rest or insomnia. I did not catch any complaint of a headache so to me that throws out AMS. My one question though, what happened to your body after you got off the mountain? How did you feel when you got back to your car?
I also don't think it was heat related (heat exhaustion or heat stroke) due to no account of change in level of responsiveness or mental status which are key symptoms. Also no cramping or complaint of feeling chilled (skin: pale, cool and clammy).
My conclusion without seeing the patient in the field would be general fever. This could account for the feeling of being overheated and the feeling of dizziness and exhaustion. Its hard to say without actually seeing the patient and getting some key components, but that is my guess. Or heck, it could have been a weird combination of some of the stuff discussed plus who knows what else!
skydzntcare - I'm glad that you are doing ok now and glad you took the time to share your story for us all to learn from. It is important to know your body and know your limits. I hope you continue to stay safe in the mountains.
Derek - WEMT