One of the ways that we holistic healers treat a symptom is similar to the theory of the "hair of the dog that bit you".  Expose 

To understand the ECS, it first helps to understand what homeostasis is.
Basically, homeostasis is your body's efforts to keep everything in the right zone. It tries to keep your internal environment stable and optimal no matter what's going on in the environment around you. Think of all the gauges in the dashboard of a car or airplane. Those all tell the operator whether things are—or aren't—operating in the proper zone.
Just like the electronics in a car or plane, your body works continuously to monitor important levels and functions in your body. Is your temperature too high, too low, or just right? Are your hormone levels what they should be? Is your heart beating too fast? Do you need fuel or rest? Is too much of something building up in your bloodstream or inside of your cells?
When something is operating outside of the right range, your body activates the ECS to help correct it. So when you're really hot and begin to sweat, thank your ECS for working to cool you down. Stomach growling? That's your ECS helping remind you to eat because you need fuel.
The ECS does this via cannabinoid receptors found in select tissues. We have (at least) two types of cannabinoid receptors:

• CB1 which is in the central nervous system (brain and nerves of the spinal cord)
• CB2 which is in the peripheral nervous system (nerves in your extremities), the digestive system, and specialized cells in the immune system

Cannabinoid receptors are believed to be among the most plentiful in our central nervous system, and some researchers hypothesize that we could have a third, undiscovered one, as well.
Through those receptors, the ECS helps regulate a lot of important functions, such as:

• Appetite
• Digestion
• Immune function
• Inflammation, including neuroinflammation
• Mood
• Sleep
• Reproduction/fertility
• Motor control
• Temperature regulation
• Memory
• Pain
• Pleasure/reward

Your body activates the ECS with precision so that it impacts only what it needs to. For example, if your reproductive hormones are out of whack, it will work to regulate them without altering your digestion or immune system.
Then, once the endocannabinoids have done their job and brought things into balance, certain enzymes come along to break them down and prevent them from going too far and upsetting the balance in the opposite direction.
It's a precise response.
That's different from what happens if someone smokes marijuana and floods their system with cannabinoids. Then the drug has wide-ranging impacts on physiology, some of which may be beneficial while others may be harmful.
Homeostasis is essential to our health and survival, so when the ECS isn't working properly, it can cause a lot of problems for you. 
Because cannabis products can stimulate activity of the ECS, they're obvious targets for potential treatments, and a ton of research is going on around the world. We also have medications made from synthetic (lab-created) cannabinoids, such as the drug nabilone.
We're already seeing a lot of research on cannabinoid-based treatments and we're likely to see more as we gain a better understanding of the system and the substances. Changes in legal status have also driven research.