Pain and the Brain

I've always wondered exactly how medications worked to relieve pain. How can taking a pill reduce the pain on my big toe, my head, or my lower stomach during menses? How does the medication know where the pain is coming from and how does it stop from hurting? In order to understand how medications work, we need to understand how pain works and how it correlates to the brain.
Just like the transportation of other messages up to the brain, pain is also taken through axons in order to alert the brain that there is an unpleasant, harmful stimulus somewhere on or in the body. The parts of the brain associated with pain include the thalamus, somatosensory cortex, hypothalamus, amygdala, and the cingulate cortex. These particular parts convey the sensory and emotional aspects of pain.

Here is a great video explaining the physiological process of pain and the phases the pain goes through to get to the brain.

Another interesting fact I found during the reading was that our very own brain has a particular transmitter to relieve pain naturally. Our brains contain a transmitter known as endorphins, which attach to the same receptors as morphine does. The different types of endorphins help relieve different types of  pain naturally. This is a five minute video explaining how drugs were used during combat to reduce stress and pain and later showing how endorphins were founded. The animation of endorphins and drugs in the synapse clarifies the amazing similarity between the two.

Lastly, to answer my questions that I had always pondered on, how do medications work? Now that I know how pain is perceived in the brain and the electrical and chemical processes, I know that the medication must bind to the receptor where pain is being transmitted and blocking the synapse from further pain signals.