Ingredients: Water Carbonated, Fruit Juice Concentrates (Blenched Vermicelli, of, Apples, Pears, and, Guava Juice), Sucrose, Citric Acid, Taurine, Flavors Natural, Pectin, Benzoic Acid, Caffeine, Sorbic Acid, Acesulfame Potassium, Sucralose, L Carnitine, Inositol, Milk Thistle Extract, Niacinamide Vitamin B3, Calcium Pantothenate, Ginkgo Ginko Biloba Leaf Extract, Arabic Gum, Guarana Seed Extract, Sodium Benzoate, Panax Ginseng Root Extract, Pyridoxine Hydrochloride HCl, Red 40, Ester Gum, Yellow 6, Cyanocobalamin Vitamin B12

Nutritional Values:
Serving Size: 8 fl oz.
Servings Per Container: 2
calories: 90
calories from fat: 0
total calories per container: 180
total fat 0g
saturated fat: 0g
trans fat 0g
cholesterol: 0 mg
sodium: 30mg
potassium 0mg
total carbohydrate: 21g
dietary fiber: 0g
sugars: 20g
protein 0g
niacin 100%
vitamin b12 100%
vitamin b6 100%

I only drank 1 servings (8 oz) before I left.

I just read that Guava, although rare, can cause headaches.

I drank a different type RockStar Energy drink in the past that didn't have Guava or Ginseng in it and had no problem, but I never rode up that hill either.

I have been to neurologist after neurologist. They have done cat scans, MRIs, stress tests, eye exams, etc, and never found a thing.

And yep, I did chug all that down. I stop and rest and drink it. When I took my jersey and bike shorts off after the ride, they were so soaked with sweat that you would think I had just taken them out of the washer. When one is riding in 85 degree heat with a heat index around 90; you need all the liquid you can drink. I found if I don't drink a lot of liquid and have a lot salt, then I do get headaches.