The brain chemicals effecting the addict's judgment are normally dopamine, serotonin and other associated hormones. Suppose we take cocaine as an example. The user in question will administer a small amount of cocaine, which as a result will dilate the amount of dopamine around the body causing extraordinary satisfaction. But what goes around comes around, thus as the abused drug reduces, the addict will then feel despondent or miserable and will thus compel themselves to continue the pattern.

Even after this pattern is first executed it will require increasing amounts of the abused substance to fully produce the initially desired reaction as the brain begins to adapt to the abused substance. The brain chemistry will change intensity and the addict will never again be able to get as self-content as he or she did initially and he or she spends what is left of their energy searching for an even better high without success. With perpetual high-dose abuse the desirable effects of the drug will decrease and the unwanted consequences will be all that the addict feels. It isn't only mind-altering substances that the general populous are able to find themselves uncontrollably addicted to.

Practices along the lines of gambling, browsing the Internet, online games, sexual activity, pornography, a person's habit of work and even naturally healthy hobbies along the lines ofathletic training can also help a person's body to produce the endorphins in the brain that often trigger addiction-related recurrences of action.