September News from Last Door

THE EFFECTS OF DRUGS ON YOUR BRAIN

In the August newsletter I explained some of the physiological reactions in the brain that take place with substance abuse. Drugs which are abused resemble the natural neurotransmitter substances found in our bodies. If they caused no response in our systems, they would not be addictive.

Every psychoactive substance (such as alcohol, benzodiazepines, and opiates) acts on specific sites, or receptors, in the brain and elsewhere. Simply put, the substance is like a "key" while the receptor is the "lock." This key-in-lock action is what causes the nerves to fire and results in the psychoactive, or "high," response that comes from using addictive substances.

All addictive drugs affect the production, release, or elimination of the neurotransmitters which, in turn affect the functioning of different parts of the brain. The part of the brain that is targeted determines the resulting feeling or side effects. For example, cocaine and amphetamines increase the level of dopamine which affects the pleasure area of the brain. This results in the feeling of euphoria or "high".

During intoxication, the neurotransmitter levels are strikingly elevated giving the desired sensation. But chronic use of these substances profoundly affects the processes in the brain by depleting the level of neurotransmitters. These kinds of changes inevitably result in physical and mental symptoms, and changes in behaviour. The symptoms often reflect the degree to which the neurotransmitter has been depleted.

Four key groups of neurotransmitters are related specifically to substance abuse. The healthy functioning of these particular messengers is vital to our well-being and ability to experience pleasure and satisfaction, and to function in a productive manner. The four groups include serotonin, GABA, catecholamines, and endorphins and enkephalins.

Serotonin is the "feel good" neurotransmitter that gives us good moods, helps us relax and enables us to sleep. Most drugs increase the level of serotonin inducing a sense of relaxed confidence. However once the drug is stopped, the decreased level of serotonin becomes evident with symptoms such as depression, a lack of well-being and self-confidence, negativity, difficulty sleeping, anxiety, irritability and, if low enough, suicidal thoughts and rage.

GABA is the major inhibitory neurotransmitter that helps alleviate anxiety and worry and influences intellectual activity. Alcohol, benzodiazepines, barbituates and sleeping pills target GABA directly. Because of its inhibitory effects, any drug that increases the actions of GABA will decrease general brain activity and can be considered a "downer" or depressant. Without sufficient GABA, people feel stressed, pressured, impatient, on edge, nervous and irritable. At very low levels, panic attacks may occur.

The catecholaminesare a group of excitatory neurotransmitters that govern our abilities to pay attention and to experience excitement, pleasure and the sense of reward. Dopamine is in this category and is known as the "euphoria" neurotransmitter. To cope better in life, some people turn to stimulant drugs such as cocaine and amphetamines, and thrill seeking activities to try and increase the catecholamine neurotransmitters. The chronic use of such stimulants depletes the catecholamines leading to symptoms such as depression, excessive sleeping, difficulty experiencing pleasure, and flat moods and apathy.

The endorphins and enkephalins are two groups of structurally similar neurotransmitters that are powerful natural pain killers. Alcohol, heroin, methadone and opiates target these neurotransmitters in particular, resulting in a relaxed, numb or comforted feeling. Low levels may result in feeling emotionally raw and over-sensitive to physical pain.

While abuse leads to imbalances of the neurotransmitters in the brain, proper nourishment of these brain messengers can restore them once again to healthy levels of functioning. When added to a program including psychosocial support and good diet and exercise, a person is likely to enjoy good physical and mental health.

Dr. Cynthia Isles
Naturopathic Physician