We have coined the word moodifier to mean any substance or drug capable of causing strong mood swings. Moodifiers may be ingested or otherwise taken into the body, or manufactured by the body itself.

To understand moodifiers, it is important to understand the basic mechanism of all thinking and feeling, which occurs at the synapse, a microscopic gap between nerve cells. It is here, in various parts of the brain and throughout the body, that decisions are made, sensations are interpreted, thoughts are recorded, and communication between cells of vital organs takes place.

A Nerve Cell

When a nerve cell is stimulated by another nerve cell or a sensory receptor, the message is conducted to the end of its aXon(s) by a cascading electrochemical process. There tiny sacs called synaptic vesicles each release thousands of neurotransmitter molecules into the synapse. The synapse is about a millionth of an inch wide. The neurotransmitters cross the synapse, and some may fit, like keys in keyholes, into receptor sites in the dendrites or (sometimes) cell body of the next nerve cell. If enough of them find receptor sites, the next nerve cell will fire, and so on.

Exogenous Drugs

When a moodifier, like heroin, is eaten or smoked or injected, it is called exogenous, meaning coming from outside the body. Heroin in the body breaks down into morphine, and the morphine winds up crossing many billions of synapses between brain and other nerve cells in your body. Its drugeffect comes when lots of these molecules find certain kinds of receptors, like the μ (or mu, for morphine) receptor. These signals alter the perception of suffering caused by pain. This is why morphine (and its synthetic imitators) are used following major surgery.

Endogenous Drugs

Morphine is derived from the opium poppy, which for many centuries has been known to alleviate pain. But why would the body have receptors just for the product of this one plant? The answer is very important to the study of addiction. If you find a key on the sidewalk and try it in enough locks, you will eventually find one it will open. It will probably not be the lock it was designed for. It is just close enough that it works. In the body, morphine is the “accidental” key; the natural one is a class of neurotransmitters called endorphins. These are “drugs” that are manufactured within the body, and their actions are very similar to morphine. They are called endogenous, meaning that they come from within the body itself.

This bombshell has far-reaching implications for the treatment of addiction. It means that people can become addicted not only to powerful neurochemical imbalances induced by drugs like heroin and alcohol but also from drugs created within the body. All that an addict must do is find some way to produce quantities of these endogenous drugs that are well above the natural levels the body needs for proper functioning.

Rating Moodifiers

Even when only alcohol, narcotics, and certain other drugs were considered mood-altering, it was difficult to compare drugs based on their addictive potential. Now that even common caffeine is recognized as having a moodifying effect, we need some model to get a handle on how we view these various drugs, whether administered from outside the body or produced by the body itself.

We will borrow a rating scale familiar to almost everyone: the motion picture rating scale. just as with movies, this will be a judgment call; your experience may differ considerably. And due to individual differences, any certain drug might be more accurately placed in a different rating when it is present in your body

X-rated drugs These are moodifiers that usually have a high potential for addiction and are generally not needed to maintain good health. In fact, they may be connected with severe health costs, to the individual and to society. We believe that this rating includes alcohol, heroin, cocaine, tobacco, marijuana, and many other illegal drugs.

R-rated drugs Moodifiers that have a high potential for addiction but also have legitimate uses for health care include analgesics (painkillers), tranquilizers, depressants, stimulants, and many other prescription drugs that are known for their mood-altering properties. People with known addictive tendencies should use these drugs only if genuinely medically needed, with no fooling, and then they should take measures to insure they are used only as necessary.

PG-rated drugs There are many drugs and other substances that are generally not thought to have extreme mood-altering properties, but often do wind up being abused by addicts and sometimes by other people. We would include here sugar, caffeine, antidepressants, laxatives, diuretics, and many over-the-counter (OTC) medications, and the body’s response to activity like sex, gambling, or high risk.

G-rated drugs Finally, even those substances that are often considered natural and even healthy, when abused and incorporated into the addictive cycle can become addictive moodifiers. This might include the chemistry your body produces in response to exercise, excitement, hunger, romance, and even religious behavior.


Some drugs depress the sympathetic nervous system. This is the part of the central nervous system that tells the body it is time to be alert, to do things, and to be concerned or worry. A depressant drug dulls or reduces those signals.

Alcohol This is the moodifier that most people relate directly to when you mention addiction, treatment, and recovery. It is a very powerful and dangerous drug.

Alcohol is exempt from control by the Food and Drug Administration; it is controlled by the Bureau of Alcohol, Tobacco and Firearms. If the FDA had jurisdiction, it would be available only by prescription, and then it would be difficult to justify it as a medicine.

Sleeping potions Barbiturates (like Seconal, Tuinal, and Nembutal) and other medications commonly used as sleeping pills (like Quaalude, Placidyl, and Dalmane).have a depressant effect similar to alcohol.

Heroin Many analgesics (painkillers) are depressant drugs. Heroin is refined from morphine. In fact, heroin was once promised as a cure for morphine addiction because it was thought not to be addicting. While morphine and other opiates are still used as pain-killers, heroin has no approved medical use in the United States.


The “major tranquilizers” often have a beneficial effect on people with severe mental disorders. The “minor tranquilizers,” on the other hand, are usually unnecessary, and highly addicting. When someone tells you they are not addictive, remind them that it was only a few years ago when almost all physicians thought that Valium was not an addictive drug, and it was the most prescribed drug in the United States. We would rate tranquilizers as PG, with more legitimate uses for the major ones.

Sugar As a mood-altering drug, sugar seems to most resemble tranquilizers. When used in quantities or concentrations high enough to produce even a mild moodifying effect, we would rate it at least PG, depending on the individual’s sensitivity to it.


Stimulant drugs actually depress the parasympathetic nervous system — that part of the central nervous system that works in balance with the sympathetic system. While the sympathetic nervous system tells the body to get up and do things, the parasympathetic system says slow down, relax, and enjoy. If this parasympathetic system is depressed, the sympathetic system has less competition, so you feel more awake, alert, and ready to go.

Ironically, the more you do, the less you will be pleased with it, owing to the depression of the parasympathetic system.

Caffeine The most common powerful stimulant is caffeine. It is not only addictive but its withdrawal produces headaches, lethargy, and other discomfort.

Cocaine This is a stimulant that also has the capacity to distort sensual perception, and is also highly addicting.

Diet pills Diet pills, like the over-the-counter drugs based on propanolamine, can produce addictive responses.

Nicotine The drugs in tobacco, including nicotine, share with cocaine the dubious distinction of being the most addicting drugs known to humankind.

Excess protein Eating too much protein also produces a stimulant effect, and frequent bingeing on protein can produce an addictive sensitivity to it.


These are drugs that often have a positive effect on clinical depression. Examples are Elavil, Sinequan, and Prozac. They are not often abused, and they are very useful if depression is severe. They are also sometimes prescribed when they are not needed, and they should be used with caution, especially for people with an addiction history.


These include marijuana, LSD, and any other drugs whose major action is to distort the perceptions or the thinking process.

The basic info about the various moodifiers still needs work. It is mostly unchanged since 1992.

Moodifiers, see also: Abstinence, Addiction, Alcohol, Binge history, Biochemistry, Chronic pain, Cocaine, Crisis, Drugs, Excitement, Heroin, Inhalants, Judgment, Marijuana, Moderation, Neurotransmitters, PEMS model, Physical aspects, Powerlessness, Progression, Purging, Relapse & prevention, Sex, Sugar, Tolerance, Weight, Withdrawal.

Updated partially, 6 Sep 2015

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Addictionary 2 by Jan & Judy Wilson

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