Addictive Substances: The Anatomy of Drug Addiction

Last Updated: June 4, 2020

Not a single one of the 24 million addicts in the country started using drugs with the intent of becoming such. Some try them under peer pressure, thinking it will only happen once, while others resort to them to suppress unpleasant emotions or symptoms of mental disorders. Still others are born into an environment, in which drug usage is prevalent, where family members can abuse or be addicted to drugs. There are no set criteria at present to establish whether someone is likely to start abusing or become addicted to a controlled or illicit substance.

What is Drug Addiction? Most Drug Users Don’t Know

Illegal drugsFrequently, we don’t suspect a friend or loved one is struggling with this complex and painful disorder. The official definitions of drug addiction? It is defined as a chronic, relapsing brain syndrome characterized by compulsive searching for and using the substance despite obvious negative consequences. These drug problems often last long and result in behavior that is harmful both to the individual abusing the drug and to those around him or her. And what is a drug? Officially defined, it is a substance which has a physiological effect when introduced into the body. By that criteria, even water qualifies as one. Clearly, the official definitions leave something to be desired. Or do they? After all, what is drowning if not a water overdose?
The type of substance is key to the issue of drug addiction. OTC drugs, like Aspirin, have a very low addiction potential because their physiological effects are minimal, and sometimes not particularly positive (Aspirin causes stomach acid). Marijuana and stronger painkillers, on the other hand, bring about feelings of relief, calmness, and other desirable sensations, and their addiction potential is higher. A user can become dependent on these very easily.

Causes and Consequences of Addiction: Misconceptions

Drug addiction is stigmatized because awareness of the effects is higher than of the causes. Addicts are often labeled as weak, selfish, and lacking ambition and willpower. The truth is that this affliction transcends race, gender, socioeconomic status, and religion. Anyone can become addicted to drugs. Psychologists have carried out testing of personality traits for decades to see if certain traits could make a person more likely to become addicted, and personality inventories have shown these people tend to score high on impulsivity and neuroticism scales, meaning they are more impulsive and anxiety-prone than people who don’t abuse or get addicted to drugs. However, it remains ambiguous as to whether people started to score high on these scales because they were impulsive or neurotic to begin with or became that way after drug addiction took hold and these above-average scores actually reflect the effects of drug addiction on their brains and not their innate personality traits. An additional confounding factor is that not all psychologists or organizations take the time to actually make sure the people taking these tests meet addiction criteria as set out in the DSM or ICD, depending on whether the studies were or are being carried out in the United States or Europe. It would seem people with ineffective stress combating techniques are more prone to becoming addicted, as well as members of the social groups listed below.

How Common is Drug Addiction?

According to a 2012 survey, 23.9 million Americans ages 12 and up are addicted to drugs, which equals about 9 percent of the US population. Drug addiction is more pronounced among military veterans, college students, professionals with demanding careers, and people suffering from mental or chronic pain conditions. Members of the last group may abuse or be addicted to prescription pills. 9% is markedly higher than one would expect, as the stereotypical drug addict is a disenfranchised individual (a member of a minority group) and/or someone who comes from a “broken home.” In reality, this isn’t the case for everyone who becomes addicted to drugs. For example, businesspersons can turn to them to cope with work-related stress and the stress of a high-pressure career.

Drug Use and Abuse: Effects on the Brain

Addictive substances affect the release of various neurotransmitters in the brain, depending on the substance of choice. Users will experience euphoria and other positive sensations. When incidental use has become drug addiction, certain release patterns will form. With time, the brain begins to release less and less of these pleasure-inducing neurotransmitters (mainly dopamine and serotonin), motivating the user to take higher and higher amounts to be able to experience the same effects. This is known as tolerance. When they don’t take the substance or take less of it for whatever reason, they will experience unpleasant withdrawal symptoms from the unfulfilled need. Addictive drugs alter the functions of various hormones and neurotransmitters, which control the way one perceives happiness itself. Drug users begin to think they need the substance, and it can transform into a physical need in more severe cases. A user will do anything he or she can to obtain it, even though they are aware of its negative consequences. Sometimes addicts will start spending less time working or doing things they used to enjoy with friends or loved ones and more time in efforts to access the substance or recover from a hangover. The drug becomes the cornerstone of their lives.

What are the Most Common Types of Drug Addiction?

Aside from marijuana and painkillers, these are the most frequently abused substances and types of drugs:


This is one of the most commonly used and abused illicit substances. It is classified as a Schedule II drug under the Controlled Substances Act alongside morphine, PCP, methamphetamines, methadone, and several other substances with high addiction potential. Schedule II substances can cause severe physical and psychological problems despite having some accepted medical uses. Cocaine is a powerful stimulant that is snorted as a powder, but it can also be found in rock form. The rock form is called crack. It is derived from cocaine powder combined with water and (usually) baking soda. After baking soda and cocaine are combined, the mixture is brought to a boil, and a solid forms. It is then cooled down and broken into smaller pieces, which are sold as crack. The name comes from the crackling sound one hears when heating and smoking the substance. Crack is extremely concentrated, and highly addictive as a result. Some people have become addicted after smoking it just once.


Methamphetamine or crystal meth is one of the most addictive drugs. Its name is derived from the form it is produced in – clear, pale blue, pink or white crystals. This man-made drug is amphetamine’s stronger cousin, flooding the brain and bringing it to produce what has been estimated as a thousand more times dopamine than it would during an activity like sex. The euphoric blast one experiences when inhaling or injecting it remains in the system for a relatively long period of time, rewriting the brain’s pleasure and reward centers and paving the way for painful addiction. It truly is a vicious substance, but it isn’t a Schedule I drug because it has an accepted medical use – it is sold as a prescription drug under the name Desoxyn, used for treatment of attention deficit hyperactivity disorder and severe obesity.
Meth can destroy dopamine receptors in the brain over time, and unbridled use of this substance causes permanent cognitive damage. Signs and symptoms of meth addiction include weight loss, severe dehydration, lowered sex drive, high body temperature, osteoporosis, abscesses caused by injecting the substance into the skin, and sleep deprivation. In one of the later stages of drug addiction, behavior will become erratic. Common forms of drug addict behavior and peculiarities include severe paranoia, aggression, retreating and becoming socially isolated, and hallucinations. A sign of addiction to this substance might be risky and impulsive behavior that is out of character. Understandably, none of these forms of behavior are present upon first-time use. When people take meth for the first time, they feel very active, euphoric, and sociable. Nothing can compare to the first experience, including any subsequent exposure to the substance. This compels drug users to relentlessly chase after this first experience in a desperate attempt to relive it (i.e. “chasing the dragon.”)


3,4-methylenedioxymethamphetamine (MDMA), better known as Ecstasy, is used by millions of people nationwide. It gives the user a feeling of well-being and distorts their perception of time and space. MDMA started becoming popular as a party drug in the 1980s, but has gone far beyond the party scene since then. According to the National Survey on Drug Use and Health, more than 18 million people in the United States have taken ecstasy at least once in their lives. Researchers have identified a number of negative, potentially serious side effects of drug use, such as body temperature increase that can be fatal in some environments. What is more, ecstasy tablets contain a number of other substances or drug combinations apart from MDMA, which can be even more dangerous. Researchers have found X pills bought on the street to include PCP, caffeine, methamphetamine, ketamine, diet substances like ephedrine, synthetic compounds found in bath salts, cough suppressants, and heroin. Sometimes the pills don’t contain any MDMA at all. The DEA placed MDMA on the list of Schedule I drugs in 1985, which are substances with high abuse potential and no accepted medical use, where it has remained ever since.


When the subject of drug abuse and addiction comes up, heroin immediately springs to mind. Heroin is made from morphine, which is in the class of opiates and is made using seed pods of opium poppy plants grown in South Asia, Mexico, and Colombia. Heroin comes in brown or white powder form or a sticky substance that looks like tar. Also called smack and hell dust, among other things, heroin can be injected, smoked, snorted or sniffed. Speedballing is what it’s called when it is mixed with crack.
Heroin rushes into the brain and binds to opioid receptors in areas that modulate feelings of pain and pleasure and control breathing, sleeping, and heart rate. Prescription pills like Vicodin and OxyContin are reported to have similar effects, and these may serve as gateway drugs – four out of five heroin users in the United States, including those currently receiving treatment, started by abusing prescription opioids.
Short-term effects of heroin use include surges of energy and euphoria, clouded mental functions, and drifting in and out of consciousness. People abusing heroin over the long term may begin to suffer from sleeplessness, heart lining and valve infection, stomach cramps and constipation, skin abscesses, liver and kidney disease, lung disease, sexual dysfunction (men), amenorrhea (women), depression and other mental disorders, damaged nasal tissue if the substance is sniffed or snorted and collapsed veins if it is injected. People who inject it face the additional risk of becoming infected with HIV or hepatitis C, which can be transmitted when sharing needles or other drug use equipment. Finally, as one of the most addictive drugs, heroin carries a high overdose risk, and heroin overdoses have increased significantly in recent years.


LSD (D-lysergic acid diethylamide) is one of the most commonly used and addictive hallucinogens along with mescaline, mushrooms and ecstasy. It is frequently combined with other substances, which makes it more dangerous. Like the other substances in its class, it causes a sense of time and space distortion that some people find appealing. It can cause feelings of euphoria and excitability, although the reaction to the pill depends on the user. Wild mood swings are frequent, and it is also possible to feel two mutually exclusive emotions at once, such as euphoria and rage. Paranoia and aggressive behavior are common. Emotions and sensations may cycle swiftly from one to another when the person is using, and with time, this will start to happen even when the person is no longer under the influence because the substance changes the “wiring” of the brain, leading to chronic emotional instability.

Prescription Drug Addictions: Risky Substances

We speak of prescription pill abuse or addiction when a drug is used in a way different from what the prescribing physician intended. The three most commonly abused and addictive types of medication are painkillers, depressants, and stimulants. Depressants include benzodiazepines such as Xanax, sedative hypnotics (sleeping pills), barbiturates, and certain anxiety medication. Xanax, for example, is an addictive drug designed to treat people suffering from panic and related anxiety disorders. Its effects can be felt in minutes.  Surprisingly, even antidepressants are now being classified as potentially addictive drugs. Prescription drug abuse and addiction can have tragic consequences – unintentional overdoses have increased fourfold in the past two decades.   


As the name suggests, inhalants are substances that have physiological effects when inhaled. These can include aerosol sprays, paint fumes, solvents (liquids that become gas at room temperature), gases, and nitrites (prescription medicines for chest pain). Inhalants deliver a very quick high. As they are quick to wear off, however, they are often combined with other drugs or alcohol to enhance their effects. Most parents are concerned about illicit substances such as marijuana, some narcotics, cocaine, and LSD – and rightly so – but the dangers posed by common household products should in no way be ignored. Children can inhale glue, nail polish remover, hair spray, deodorant spray, lighter fluid, fumes from whipped cream canisters, and cleaning products. Clearly, drug addiction is not the only risk in these cases. Data of recent national surveys show that nearly 21.7 million Americans aged 12 and older have inhaled one of the above-listed products at least once. Almost 15% of 8th graders have used inhalants. A young drug user abusing inhalants will sustain irreparable brain damage over time, especially if they are combined with other substances.


Recent data show that up to 30% percent of people who smoke marijuana may have some degree of marijuana use disorder. What is more, people who start using it before the age of 18 are six times more likely to develop this disorder than adults are on average. Marijuana comes from the cannabis plant and can also be ingested. It is the main ingredient in space cake. Cannabis oil can be inhaled using a vaporizer. The most common effect of this plant is a warm, pleasant sensation of peacefulness and happiness, which motivates a person to keep using it. However, some people have an aversive reaction to marijuana, which involves severe paranoia and other unpleasant sensations. This will, understandably, deter them from future use. Marijuana has become legal in quite a few states for its medicinal properties. It has been proven to help improve the outcome of glaucoma, an eye illness involving damage to the optic nerves and causing permanent blindness if left untreated. However, long-term, uncontrolled marijuana use has also been known to cause severe lung diseases, including lung cancer, damage to the hippocampus, which is implicated in short-term memory function, high blood pressure and sexual dysfunction in men.

New Psychoactive Substances

These legal substances are proliferating at an exponential rate, posing a significant risk to the health of the public and a challenge to national drug policy. New psychoactive substances are also known as bath salts, legal highs, and research chemicals. They are defined as “substances of abuse, either in a pure form or a preparation, that are not controlled by the 1961 Single Convention on Narcotic Drugs or the 1971 Convention on Psychotropic Substances, but which may pose a public health threat”. Many of them are not new despite their name, having been synthesized over four decades ago. Risks of NPS range from mild agitation and aggression to seizures, acute psychosis as well as potential drug addiction. The main substance groups of NPS are synthetic cathinones, aminoindanes, synthetic cannabinoids, phencyclidine-type substances, phenethylamines, tryptamines, piperazines, plant-based substances such as kratom, salvia divinorum and khat.

Drug Addiction Treatment: Is There Hope?

familyIt is possible to get drug addiction treatment in rehab centers regardless of which state one lives in. Rehab clients are offered a wide variety of drug addiction treatment methods to choose from. There are tens of thousands of outpatient and inpatient rehab centers, 12- and non-12-step programs, and traditional or holistic therapy centers across the country. Clients can choose to attend a center close to home or travel for rehab. Drug users often do not realize they have a problem until the substance has become the most important part of their lives. Family members and friends are frequently the first to notice that things have gone too far. Getting and staying clean necessitates an integrative approach. First, the user needs to undergo detox to get the drugs out of his or her system. Withdrawal is a dangerous stage of the process. An addict should never attempt to detox alone as withdrawal symptoms can be fatal, and withdrawal medication needs to be administered by a doctor. Although it is a challenge to get and stay sober, it can be achieved, and many people have been able to kick the habit after undergoing treatment.

Page Sources

  1. Frances, R. J., & Miller, S.I. (1998) Clinical Textbook of Addictive Disorders, Second Edition. New York, NY: The Guilford Press.
  2. National Institute on Drug Abuse. (2014). DrugFacts: Nationwide Trends. Retrieved on July 23, 2015, from:
  3. National Institute on Drug Abuse. (2013). DrugFacts: Understanding Drug Use and Addiction. Retrieved on July 23, 2015, from:
  4. National Institute on Drug Abuse. (2015). DrugFacts: Treatment Approaches for Drug Addiction. Retrieved on July 29, 2015, from:

Published on: September 25th, 2015

Updated on: June 4th, 2020


Leave a comment

  • Shar
    OMG I can’t tell my fam. Has anyone everyone went through treatment on their own and succeeded.
  • Joseph Mee
    If you love them then why lie if your motives are for getting sober?..After any shock they will come round and you can get support from them.Stay close to revovery and get to as many meetings as you can!Good luck