First of all, I know this post is over a year old, but I wanted to get the correct information out there for anyone who stumbles onto this page because tink2's information is wrong. I went to rehab for oxycontin addiction, and I was taught by doctors exactly how opiates affect your brain. Here's how it goes, and I'll try to put it in lamen terms the best I can:
When Oxycontin enters the brain, it causes the stimulation of a "feel good" neurotransmitter called dopamine. Your body naturally produces dopamine, and the body's natural dopamine comes in many different "shapes" if you will. In order to produce the feel good effect, neurotransmitters are released and fit into specific receptor sites according to their shape (Imagine putting to puzzle pieces together). Thus when they "connect" to the receptor sites, the feelings of pleasure happen. With Oxycontin, it stimulates the production of dopamine neurotransmitters, however this process is different from the natural process because instead of producing a wide variety of "shapes", the brain is flooded with dopamine that is only one shape. At first it feels good, because of the overwhelming amount of dopamine. However, with continued use, the body adapts to the overwhelming amount of the "single shaped" neurotransmitter, and begins to create more receptor sites which match that neurotransmitter. This is why users begin to build a tolerance, because as more receptor sites are created, there needs to be a greater presence of those "single shaped" neurotransmitters in order to attain the same desired effect. Thus, without the presence of the excess dopamine, there is a greater number of unfilled receptor sites, which in turn causes the depression. The body will continue to produce the same amount of dopamine naturally, however the bodies dopamine comes in diverse shapes and the receptor sites created from the oxycontin use will only take the specific "shape" neurotransmitter that oxycontin produces. The body does produce that "shape", but a much less amount. If users stop using oxycontin soon after the new receptor sites are created, they will disappear and with time the brain will return to its normal amount of receptor sites.
If the Oxycontin use continues for a greater length of time, long term depression becomes a factor. This is because with constant oxycontin use, the newly created receptor sites are being constantly used. With prolonged use, the some of the receptor sites become permanent, or at least take months or years to disappear. This is why it long-term opiate addicts have such a difficult time kicking the habit, because they have to put up with depression that lasts months or years, and in some cases a lifetime.
I used Oxycontin for 10 months, five months of which was everyday use, and around day 50 of my recovery, the last of my depression was gone and I felt normal again. Thus, my opinion is that every year of use requires 2 months of sobriety until one is feeling depression-free, give or take a couple months. I suggest to anyone who is using oxycontin to quit immediately because, like cigarettes, quitting becomes exponentially harder as time goes on.
Addiction Recovery Tracker