Glaucoma is a group of eye conditions in which fluid builds up in your eye causing gradual vision loss. Ocular migraine Ocular migraine usually refers to a type of migraine that can cause temporary blindness in one eye.
Increased Blood Pressure. The combination of caffeine and ephedrine can increase your blood pressure. Ephedrine and caffeine stimulate your sympathetic nervous system by increasing neurotransmitters, such as norepinephrine. This stimulant effect can increase your blood pressure by constricting your blood vessels. This is why many diet pill formulas, often called an ECA stack, contain ephedrine, caffeine and aspirin to thin your blood to offset the blood vessel constriction.
There are two theories. The first: A headache happens when the body releases adenosine, a chemical that inflames blood vessels, causing throbbing and pain. The caffeine in coffee puts the kibosh on adenosine and helps constrict blood vessels. The second theory posits that caffeine increases the effectiveness of pain relievers, helping the body absorb them more quickly for faster relief.