Iris (Definition) The iris is a structure within the eye that helps reduce the amount of light that reaches the retina. The iris is known as the colored part of the eye, and can be blue, brown, or any color or combination of colors in between. The iris is the portion of the eye that responds to light stimulation. ...Read more.
Scientists also speculate that caffeine may provide a mood-boosting effect that helps ease pain. Regardless of the mechanism by which it works, the data does indicate that caffeine does indeed make pain medications more effective and help ease pain.
While it is certainly possible that heavy consumption of caffeine may lead to rebound pain, occasional use is generally helpful. The research agrees. In brief: It usually helps. In my practice, with my patients, I have found that caffeine usually enhances the effects of other medicines used to treat pain conditions. I have regularly seen this benefit for tension headaches, migraine headaches, and chronic pain conditions.