November 2019 Print

Drug Addiction, Abuse, and Dependency

By Ross Keiser, M.D.

Any discussion of these issues should start with two disclaimers. First, the research and laws are rapidly changing, often politically and emotionally charged, and frequently contradicting each other. Second, the terminology and definitions vary considerably. In this article the attempt is made to provide a general overview, with the full understanding that many readers may disagree with part or all of the statements therein.

Terms and Definitions

There are a variety of definitions for drugs or substances, drug addiction, abuse, and dependency in professional literature, depending on the source, and these have changed over time. Clinically, the most commonly used definitions of these are provided in the Diagnostic and Statistical Manual of the American Psychiatric Association (DSM5), all subsumed under the heading of substance-related disorders.

For regulatory use, the most common terminology and classifications are provided by the U.S. Food and Drug Administration (FDA). In legal matters, federal, state and local statutes are used. In many instances, the definitions in laws are in contradiction to the DSM5 and/or the FDA. Among users, a wide variety of terms are used, varying by time and location, and often are rather inaccurate. For example, the term narcotics refers to sedatives, but many statutes list stimulants and hallucinogens as narcotics.

The FDA uses the term “drugs” and the DSM5 uses the term “substances.” These terms are virtually identical in terms of abusable or addicting chemicals. However, drugs can include medications which are not abused or cause addictions.

Why People Use Drugs

One of the few laws in psychology is the Law of Affect. This states that actions which are experienced as pleasurable tend to be repeated. Many people find the effects of taking various substances to be pleasurable. Therefore, they tend to repeat using them.

There are a variety of chemicals which affect the central nervous system, and some people find some of them to induce effects they like. In general, we can lump them into the categories of stimulants (uppers), depressants (downers), hallucinogens, and others. Not all people like all drugs. For example, some people like the feeling of taking uppers, others feel discomfort and edginess. Many people dislike the feelings they get when they try marijuana, but many others enjoy using marijuana.

People start using drugs for a variety of reasons. Some want to experiment with feeling different. Some feel the need to relax or unwind. Some start using due to peer pressure, or wanting to fit in, or be “cool.” Many people end up addicted to drugs because they were prescribed for pain control, weight loss, anxiety, and other medical and/or quasi-medical reasons.


In general, addiction and dependency are similar, if not the same, and will be used interchangeably in this article. However, dependency is more often used when describing substances such as drugs or alcohol, while addiction is used for substances as well as lifestyle or behavioral “psychological addiction” issues. Substance abuse can occur with or without addiction or dependency. As an example, a person who is not an alcoholic, and rarely drinks, may drive while intoxicated, which is illegal and dangerous, which is clearly abuse.

Dependency or addiction is a physiological, or physical condition in which the body of a person has adapted to a substance, i.e. chemical, so that the presence in the body has become the normal state for an individual. Some chemicals, including ethanol (drinking alcohol), nicotine (tobacco), and opioids (heroin, morphine) are considered “addictive” in that the body does conform to them in such a way. Other chemicals, such as LSD, may not be physically addicting, despite being very dangerous, and capable of being “psychologically addicting.” In a number of cases, there is disagreement whether or not a drug or substance is physically addicting.

How Addiction Occurs

Physiological dependency is a physical addiction. As noted above, our bodies have an ability to integrate some chemicals into what is called the homeostasis. That is a fancy term for balance or equilibrium. Our bodies like, and need, to keep things the same. For example, our bodies want to keep a certain temperature, normally about 98.6 degrees Fahrenheit. When our body temperature goes higher, we perspire and pant, and our skin gets red as the blood vessels dilate to cool us. When we get colder, our metabolism raises and we shiver to get warmer, and get “goose bumps” as the blood vessels constrict to reduce heat loss. All this is involuntary, our body does these things without our control or permission.

Similarly, our bodies want a certain level of blood sugar, and a certain degree of water in our systems. As we burn energy, our blood sugar drops, we get hungry, want food to replace what has been used, and bring our blood sugar back to normal. When our level of hydration decreases, we become thirsty. People who are lacking food or water for an extended time develop intense cravings, and become preoccupied with food and/or water, and will forego almost any other activity in order to obtain those.

Addicting substances/drugs can become part of our homeostasis, or normal state. It is unclear why some substances can, and some cannot. Regardless, when a person uses enough of a potentially addicting substance on a regular enough basis for a long enough time, their body adapts so that having that substance as part of their body chemistry becomes their “normal” condition. This is called tolerance. When that has occurred, if the substance is not present in the accustomed quantity, the body will crave it, just as it craves water or food when hungry or thirsty. The longer the body is without the substance, the more intense the craving.

Although this will be covered in another article, a similar process is hypothesized for addictions such as gambling, sex, exercise (“runner’s high”), and so forth. The reason for this is that certain activities cause changes and/or increased levels of naturally occurring chemicals in the brain, such as endorphins and serotonin, which people find to be pleasurable, and without which people who are used to those increased levels become quite uncomfortable.

Tolerance and Withdrawal

As part of addiction, there is a need for an ever-increasing amount of the substance to produce the desired effect. This is called tolerance. This leads to higher rate of consumption to avoid the discomfort associated with withdrawal, which is when the substance is not present in a sufficient dose, the body reacts just as it reacts to a lack of food or water. Many long term addicts require such large doses on a regular basis that would be fatal to non-addicts.

This lack of enough substance is not only psychologically distressing, but also is physically stressful. In some instances it can be fatal.

At first blush this seems surprising, as we are talking about psychoactive substances. That is, substances which affect the brain. However, anything which affects the brain also affects the rest of the body. Opiates, such as morphine or heroin, are depressants, and slow brain function and inhibit pain sensation. They also slow other bodily functions, especially digestion. When a person takes these, the digestive tract slows. The body reacts in what is known as the opponent process mechanism, and speeds the digestion, otherwise the bowels would quit moving and become impacted. As the person takes more and more opiates, the body reacts more and more strongly. When the opiates are stopped abruptly it takes a while for the body to readjust, leading to stomach cramps and acute diarrhea for a time, as well as other physical and psychological distress.

The benzodiazepines can be quite deadly in withdrawal. They slow heart rate and lower blood pressure. Withdrawal can lead to stroke without careful medical management.

Types of Substances/Drugs

The DSM5 and FDA classify drugs somewhat differently, and street drugs can be almost anything. Generally, drugs are stimulants (uppers), depressants (downers), hallucinogens, and others. Stimulants increase mental and physical activity, depressants lower those, and some find them soothing, the hallucinogens alter perceptions, and the other drugs usually yield a combination of effects.

Negative Effects of Drugs

The negative consequences of using these are divided in substance-use disorders and substance-induced disorders. In the DSM5, substance use disorders span a wide variety of problems arising from substance use and cover 11 different criteria. However, in general, these can be distilled into one idea, using when it would be wiser not to do so. This includes spending time and money inappropriately, law-breaking, and being damaging to one’s physical and mental health, and family, social, vocational, health, and educational duties.

How to Avoid Addiction/Dependence

“Just say no.” If you don’t use addicting substances, you won’t get addicted. Recreational use of drugs involves many perils, not the least of which are legal, as well as moral. An old gentleman I knew referred to himself as “an old booze fighter.” By that he meant that he felt that he had the potential to become an alcoholic (alcohol dependent). His method of avoidance of problems was simple: “When you feel like you need a drink, it’s time to lay off for a while.” Good advice. If one does use an addicting substance, stopping when the first signs of needing it is a good tactic.

One will not become an addict if one simply avoids taking very much of a drug for very long. The time varies by drug and from person to person. Also, the lower the dose, the lower the chance of addiction, and a very short term dependence is not so difficult to overcome. However, in general, addictive substance such as many pain killers and anti-anxiety agents can probably be safely taken for a few days, perhaps up to a week. Beyond that, the possibility of problems increases.

Unavoidable or Acceptable Addiction/Dependence

Certainly, many people are dependent on medications. For example, persons with intractable pain may need to be on continuous doses of addicting medications. As long as those do not interfere with meeting the obligations of duties of state, and are carefully monitored medically, this is a necessary, although an unfortunate circumstance.

Other addicting substances may also be permissible. Many people, myself included, are addicted to caffeine. I have a tolerance to it, as I do not get a “buzz” from a couple of cups of coffee, which persons not used to drinking it do experience. If I do not get some coffee in the morning, I get a headache, feel bad, and those around me suffer even more. If I thought it was a very bad thing to drink coffee daily, I would not. However, some religious groups do prohibit the use of caffeine due to its effects.

The Catholic perspective is that the use of any substance which harms the body is sinful, as the body is the temple of the Holy Ghost. Similarly, the use of a substance which leads to sinful behaviors, or to not adequately performing the duties of one’s station of life, is certainly not permitted. Questions about this should be raised with one’s spiritual advisor.


As noted above, abrupt cessation (going “cold turkey”) of use of some substances can be dangerous, and even lethal. It would be wise to consult a physician before attempting to stop using a drug.

In general, there are several ways of quitting. One is to just stop on your own, often with the support and encouragement of friends and/or family.

Self-help groups such as Alcoholics Anonymous (AA) and Narcotics Anonymous (NA) can be aids to stopping. They provide advice, mentoring (through “sponsors”), and a step by step (12-Step) program. These often are successful and are free of cost. Unfortunately, there are some theological underpinnings which can be quite problematic. Discussion with your spiritual advisor is highly recommended.

Professional treatment programs can be in the form of individual or group counseling on an outpatient basis. Psychologists, substance abuse counselors, and other counselors provide this treatment. Therapists should be carefully vetted, as many have rather questionable moral values. In my experience, many Christian counselors can be quite good, and some Protestant churches have counselors on staff, at very reasonable rates. Of course, there are some theological differences, but these usually will not present a problem, and the counselors are not likely to suggest grossly immoral acts.

More intensive treatments also are available for persons who have not experienced success with other methods. A day treatment model, in which the patients spend their nights at home, but days and/or evenings in a more intensive treatment setting, full-time residential programs, or hospital-based, under close medical management. These programs can last from 3-30 days, or longer. They tend to be expensive, but some insurance programs may defray the costs.


For many people, quitting using drugs is not so much a problem as maintaining that status. Detoxification is stopping use long enough for the body to readjust to not having the substance. The length of time necessary for this varies by substance, but always is surprisingly short. Alcohol detox is only three days. Opioids, such as morphine and heroine take about seven days. People who complete treatment programs, or even the first part of a program, are no longer physically addicted. However, the majority start using again. It is not uncommon for people to quit several times before they finally stop for good, and some never do.

It seems there are two main reasons for this. One is that the reason the person started using the drug has not been resolved. They continue to be lonely or bored, feel empty or anxious, continue to be subject to negative peer pressure, suffer from chronic pain, and so forth. As long as the underlying cause of using is not resolved, the substance abuse is likely to continue after an interruption.

The other reason is habit. As St. Thomas Aquinas noted, it takes about 22 days to make or break a habit. People are in the habit of lighting up, stopping by a tavern after work, getting high to go to activities, or to stay home. Habits generally do not disappear into a void. To remain “clean and sober” requires not only breaking the habits which were involved with substance abuse, but also to develop new alternative habits. As well, coping strategies, such as learning relaxation techniques, regular exercise, and social interaction with positive people are most helpful. Of course, regular prayer and spiritual exercises are vital.