The Hormones at Work during Addiction and Drug Rehab

Some people still believe clinical drug rehab is unnecessary, and that addiction is simply a matter of low willpower. However, substance abuse affects a variety of hormones in ways that make drug rehab a near-necessity for many addicts to get clean. The human body’s responses to frequent drug use profoundly diminish people’s abilities to act and behave as they should. In order to understand how firmly drugs can take hold of addicts’ lives, more people should learn about the hormones at work during addiction and drug rehab.


Dopamine is the main hormone responsible for our bodies’ systems of positive feedback and reward. Whenever you eat, have sex, take drugs, or do anything else you find pleasurable – your body releases dopamine. With most activities, the ensuing euphoric effects are noticeable but moderate. However, drugs like heroin and cocaine cause massive releases of dopamine which can’t be replicated naturally. When people abuse these substances, their brains become dependent on massive pleasure sensations which only drugs can provide. Even once they’ve stopped feeling the same highs, their bodies are physically dependent on the drugs they’ve abused.


Serotonin is also involved in producing a variety of pleasurable sensations, but it is different from dopamine in the ways it affects addiction. Many drugs – especially marijuana and other hallucinogens – cause the body to produce higher-than-normal levels of serotonin. This leads to feelings of calm and well-being. Unfortunately, repeated use can cause the body to reduce its response to serotonin. This phenomenon doesn’t often lead to the same kinds of physical dependencies as dopamine deficiency, but it can cause people to become depressed if they stop using. In fact, anti-depressants often work by boosting serotonin levels in people with natural deficiencies.

Epinephrine and Norepinephrine

Also known as adrenaline, epinephrine is the hormone which activates the body’s fight-or-flight response. It causes blood vessel constriction, elevated heart rate, and quickened breathing. Norepinephrine has comparable effects; though it also acts similarly to serotonin in elevating mood and gregarious behavior.

Some people – often called “adrenaline junkies” – do get hooked on the rushes they feel during high risk behaviors. However, a more pressing concern is that thrill-seekers tend to have heightened risk for drug addiction. Studies have repeatedly shown that people who are drawn to bungee-jumping, extreme sports, and other dangerous activities are more likely than others to form powerful dependencies if they use drugs.

Adrenaline is also a serious concern for drug rehab patients during and after detox. When the body is deprived of food, drugs, or other substances it depends on, heightened levels of epinephrine and norepinephrine activate the fight-or-flight response. This the reason why some addicts quit rehab early and immediately return to using drugs. Doctors are even using specialized biofeedback machines to monitor addicts’ brainwaves and identify these at-risk patients before they make bad decisions.


Cortisol is a steroid hormone released in response to stress and low blood sugar. Its main functions are to elevate blood glucose levels, suppress the immune system, and aid in the metabolism of food. Over the last several years, many researchers have also come to believe that high levels of this hormone may contribute to alcoholism. People who are genetically predisposed to chronic stress may experience even more relief from drinking than other people. Alcohol withdrawal has also been linked with high cortisol levels – an unpleasant phenomenon which drives addicts to relapse.

Addiction can take control of your body and mind, but there is still hope for lasting sobriety. Call the number at the top of your screen now for a toll-free consultation. Our dedicated addiction specialists are standing by twenty-four hours per day to help you start drug rehab and take the first steps on the road to recovery.

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