Drug addiction: symptoms, causes, and effects

Drug addiction is the compulsive need to take a specific drug regardless of the harm it causes. Also known as substance use disorder, drug addiction causes strong cravings and potentially life-threatening withdrawal symptoms when a person tries to stop.

The causes of drug addiction are a combination of genetic, environmental, and developmental factors. Many people have a genetic predisposition to develop an addiction. The brain’s reward system also plays a role here, because drugs act on dopamine.

The effects of drug addiction are physical, psychological, and social. Drugs change a person’s appearance, increase the risk of various health problems, and worsen underlying health issues. At the same time, drug addiction contributes to or aggravates mental health disorders, relationship problems, and other issues.

Characteristics of drug addiction are the inability to stop, changes in mood, appetite, and sleep, denial, and continuing to use drugs despite consequences, among others.

Treatment for drug addiction focuses on therapy, but some people may need medications too. Support groups play an important part in drug addiction treatment.

What is drug addiction?

Drug addiction is a progressive disease indicated by the inability to control the use of legal or illegal drugs. A person with drug addiction continues to use the addictive substances despite the harmful effects and consequences they cause. Nowadays, the term substance use disorder (SUD) is mainly used to refer to drug addiction.

As National Institute on Drug Abuse explains, drug addiction is a chronic disease whose main characteristic is compulsive drug-seeking. When left unmanaged, drug addiction can have a disastrous impact on a person and may even lead to death.

The classification of drug addiction was quite turbulent throughout history. The first edition of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM-1), published in 1952, identified addiction as a part of sociopathic personality disturbance. People in this category were considered ill mainly in terms of society and conformity.

In 1968, DSM-2 placed addiction alongside personality disorders and added some definitions, mainly about alcoholism. The third edition (DSM-3, 1980) and fourth edition (DSM-4, 1994) focused mainly on the differences between dependence and abuse. However, DSM-5 (from 2013) eliminated these differences and introduced the term substance use disorder.

What are the symptoms of drug addiction?

The symptoms of drug addiction depend on the specific substance abused. The main symptoms of drug addiction are listed below.

• Experiencing withdrawal symptoms when attempting to stop 
• Strong cravings for the drug
• Increasing doses to experience the same effects
• Using the drug regularly
• Spending a lot of time thinking about the drug, planning to obtain it, and using it
• Neglecting hobbies and other activities in favor of drug use
• Social withdrawal 
• Spending more time with other people who use drugs, neglecting family and old friends
• Spending a lot of money on buying drugs
• Failing to meet work or school obligations
• Engaging in risky activities such as stealing just to obtain the drug
• Reacting in anger or frustration when other people express concerns about drug use
• Lying to friends and family about drug use and the extent of the problem
• Neglected appearance and poor hygiene

What are the causes of drug addiction?

The causes of drug addiction are changes in the brain, genetics, and environmental factors. In most cases, a combination of different causes contributes to the development of addiction. 

Physical addiction to the drug occurs due to changes in the way the brain feels pleasure. The drug causes physical changes to neurons, which communicate through neurotransmitters. These changes remain for a long time after a person stops taking the drug, which explains cravings, withdrawal symptoms, and relapse in some people.

Inherited genetic traits may influence the development of addiction, Mayo Clinic reports. At the same time, environmental factors such as family attitudes or beliefs and social circles can shape a person’s perception of the drug and their attitudes toward drug use. This also plays a major role in the development of addiction.

What are the effects of drug addiction?

The effects of drug addiction are physical and psychological (mental), and they’re largely present in every aspect of a person’s life. Additionally, the effects can be short- and long-term and they vary from one drug to another.

Short-term mental effects of drug addiction or drug abuse include difficulty concentrating, aggression, irritability, hallucinations, angry outburst, and lack of inhibition. Long-term mental effects of drug addiction include cognitive decline, psychosis, anxiety, depression, paranoia, and memory loss.

Short-term physical effects of drug addiction include slurred speech, high blood pressure, elevated body temperature, shallow breathing, rapid heart rate, drowsiness, insomnia, increased or decreased appetite, and uncoordinated movements. 

On the other hand, long-term physical effects of drug addiction include kidney damage, liver damage and/or cirrhosis, tooth decay, skin damage, cardiovascular problems, infertility, seizures, stroke, higher risk of cancer, sexual dysfunction, weight loss or weight gain, appetite changes, and others. The most severe effects of drug addiction are overdose and death.

Other effects of drug addiction include relationship problems, impaired performance at school or work, job loss, financial difficulties, legal troubles, and a higher risk of engaging in risky activities and behaviors.

Why is using drugs addictive?

Using drugs is addictive because it acts on the brain and how it works. Drugs act on neurotransmitters in the brain and also affect the brain’s reward system. The neurotransmitter dopamine is in charge of the brain’s reward system; drug use releases dopamine. As a result, a person experiences pleasure, satisfaction, high, and other positive emotions. 

Surges of dopamine, however, cause the reinforcement of pleasurable yet unhealthy behaviors such as drug use. Since a person wants to experience those pleasurable emotions again, they keep using the drug.

Continued use of drugs reduces the expression of dopamine receptors. That means higher amounts are necessary to achieve the same effects.

What are the risk factors for drug addiction?

Risk factors for drug addiction are biological, environmental, and developmental. Biological factors that increase the risk of drug addiction include genetic predisposition and being a male. At the same time, adolescents and young adults are also more likely to develop substance abuse addiction.

Early first-time use of drugs is also a risk factor for addiction. According to the National Institute on Drug Abuse, the earlier people begin to use drugs, the more likely they are to develop drug addiction later on. This risk factor is both biological and developmental. It’s all due to the prefrontal cortex, a part of the brain that regulates emotions and desires and allows us to assess the situation and make sound decisions. This part of the brain is still maturing during adolescence. 

Environmental risk factors for drug addiction include peer pressure, family history of drug abuse or growing up without structure and discipline or where substance use is considered normal, and exposure to social media where the use of certain substances is glorified. History of trauma, sexual abuse, neglect, and other negative experiences in the past can also increase the risk of addiction.

What is the difference between drug addiction and drug abuse?

The difference between drug addiction and drug abuse is that drug abuse refers to any form of misuse or inadequate use of any drug or substance (including cigarettes, alcohol, and prescription medications), while drug addiction is the inability to stop using the drug despite the consequences it causes and efforts to quit. 

A good example of abusing drugs is having a prescription for some medications and then using them in higher doses or more frequently than recommended.

Abusing the drug doesn’t necessarily mean a person is addicted. When it comes to drug addiction vs. drug abuse, it’s important to keep in mind they aren’t synonyms. Although drug abuse isn’t an addiction, it’s still a cause for concern, WebMD reports. For many people, abuse leads to tolerance, dependence, and addiction.

Drug abuse is easier to stop compared to drug addiction. A person firmly decides to quit taking a certain substance. Drug addiction is more complicated than that. Even when a person decides they’re done and attempts to quit, their cravings and withdrawal symptoms are powerful and difficult to resist.

What is the difference between drug addiction and drug tolerance?

The difference between drug addiction vs. drug tolerance is that drug addiction means a person is unable to stop using substances, while tolerance occurs when the body gets used to a medicine or other substance and needs higher amounts or doses to achieve the same effect. Drug tolerance isn’t considered a mental health disorder or disease.

Over time, people build a tolerance to the drug’s effects in search of the “high” and pleasure or satisfaction they experienced when they tried it for the first time. Developing tolerance is different from one substance to another, which is why it can be short-term, long-term, and learned. 

For instance, tolerance to cocaine occurs quickly, but building tolerance to prescription drugs takes a longer time. On the flip side, learned tolerance refers to “practicing” frequent exposure to substances to the point people don’t appear intoxicated despite long periods of use.

Drug tolerance can lead to addiction. However, not every person who builds tolerance to a substance or medicine is automatically addicted to it. Some people don’t become addicted at all. That said, tolerance should be considered a warning sign. One of the biggest symptoms of addiction is building tolerance to a drug and using higher amounts. For that reason, drug tolerance acts as an alarm for persons who aren’t addicted to reconsider their actions and stop before they develop an addiction. Or they should consult their healthcare provider regarding this problem. 

It’s useful to keep in mind that addiction to drugs causes intense cravings for the drug, Healthline explains. People with drug tolerance alone don’t have cravings for the substance. In drug tolerance, certain receptors in the body that usually activate with the presence of a drug stop responding like they used to. That’s why the body may clear the substance faster as well. At this point, scientists still aren’t quite sure why that happens in some individuals.  

In people addicted to drugs, the only way for the body can “function” normally is when the drug is in their system. This explains cravings and withdrawal symptoms.

What are the substances used for drug addiction?

Substances that can cause drug addiction are truly numerous. The substances most frequently used in drug addiction are listed below.

• Marijuana
• Prescription opioids
• Cocaine
• Anabolic steroids
• Heroin
• Benzodiazepines
• Inhalants
• Prescription stimulants
• Barbiturates
• Methamphetamines 
• Club drugs
• Hallucinogens

Below, the post focuses on some of the most common addiction drugs used among persons with drug addiction.

1. Marijuana

Marijuana is a psychoactive drug used for both recreational and medicinal purposes. Marijuana addiction, also known as marijuana/cannabis use disorder, refers to problematic marijuana use. Like with other forms of addiction, a person keeps using marijuana despite the consequences it causes.

According to a study from Nature Reviews Disease Primers, marijuana addiction affects 10% of 193 million cannabis users in the world. The CDC reports that marijuana is the most commonly used federally illegal drug in the United States. In 2019, around 48.2 million people, or 18% of Americans had used cannabis at least once. The same report also states that three in 10 people who use marijuana develop marijuana use disorder.

Chronic and repeated use of marijuana leads to tolerance and may contribute to the development of addiction. Other causes of marijuana addiction include genetic or heredity and mental health factors such as anxiety and depression.

Effects of marijuana addiction include daily cough, more frequent lung illness, increased heart rate, and nausea and/or vomiting (in some cases). Marijuana directly influences areas of the brain responsible for memory, decision-making, coordination, attention, learning, reaction time, and emotion. Marijuana addiction can impair these cognitive skills. Also, marijuana addiction increases the risk of psychosis and schizophrenia.

Marijuana addiction is diagnosed when a person meets at least two of 11 criteria from DSM-5. Some of these criteria include intense cravings, inability to decrease marijuana use, and experiencing social or relationship problems, Yale Medicine explains.

Marijuana addiction affects a person by changing their mood, appetite, and sleep patterns. Persons with cannabis addiction suffer from a lack of productivity at school or work, and they’re more likely to lose jobs due to their problems.

2. Cocaine

Cocaine is a powerful and highly addictive stimulant drug made from the leaves of the coca plant native to South Africa. Cocaine addiction is a disorder indicated by a compulsive need to take cocaine regardless of harmful effects on a person’s physical and mental health and well-being.

According to the National Institute on Drug Abuse in 2020, about 5.2 million people ages 12 and older have used cocaine in the past 12 months. In the same year, 1.3 million people had cocaine use disorder. Around 19,447 people in the United States died due to consequences associated with cocaine overdose.

Various causes contribute to the development of cocaine use disorder. These include genetics, changes in neurotransmitters in the brain, and environmental causes. Common risk factors for cocaine addiction include early aggressive behaviors, peer pressure, availability of the drug, being male, high stress, and others.

Short-term effects of cocaine use include euphoria and high energy levels. With the progression of a cocaine use disorder, a person is susceptible to various long-term effects including legal problems, incarceration, malnourishment, lung infections, scarring, nasal perforation, cardiovascular problems, heart attack, and stroke, just to name a few.

Cocaine use disorder is diagnosed when a patient meets the criteria from DSM-5.

A person with cocaine addiction is restless, frustrated, and can’t keep up with commitments at work or home. They’re constantly looking for new ways to get cocaine, which is why they engage in risky activities and end up in frequent arguments with family members.

3. Heroin

Heroin is an opioid drug made from morphine. Heroin addiction is a serious and life-threatening substance use disorder indicated by persistent heroin use regardless of consequences. People use heroin in many forms, such as injecting, snorting, or smoking.

In 2020, around 902,000 people aged 12 or older reported using heroin in the past 12 months. The same report shows that about 691,000 people from the same age group in the United States had a heroin use disorder in the past year. Heroin overdose played a role in 13,165 deaths in 2020.

A specific cause of heroin addiction is unclear. Several contributing factors are involved in heroin addiction. These include genetic predisposition, family dynamics, social circle, and deficiency in neurotransmitters that encourages people to seek the sensation of pleasure. Having other mental health problems also contributes to heroin addiction.

Besides severe problems with physical and mental health, heroin addiction causes effects such as legal problems, unemployment, homelessness, social isolation, financial problems, damage to vital organs, HIV or hepatitis, and even death.

Diagnosing heroin addiction includes thorough evaluation and assessment, like with other types of substances.

Heroin addiction affects a person through major changes in their appearance and personal hygiene. It also influences a person’s behavior and makes it difficult for them to function without the drug. This leads to problematic behaviors to continue using heroin.

4. Anabolic steroids

Anabolic steroids are synthetic variations of the male sex hormone testosterone. They’re used primarily as performance-enhancing drugs to increase muscle mass and decrease body fat. Anabolic steroid addiction is a strong or compulsive need to take anabolic steroids and experience cravings when not using them.

Evidence shows that 32% of people who misuse anabolic steroids become dependent on them.

Causes of addiction to anabolic steroids include underlying mental health problems such as body dysmorphic disorder, family history of substance abuse and addictive behaviors, and the environment, i.e., exposure to the drugs through the social circle. Physical causes such as the effects of anabolic steroids on hormones and neurotransmitters could also play a role.

Effects of addiction to anabolic steroids include paranoia, jealousy, extreme irritability and aggression, delusions, impaired judgment, and mania. Physical effects of anabolic steroids addiction include kidney problems, liver damage, heart problems, a higher risk of blood clots, and others.

Diagnosis of anabolic steroids addiction is similar to the diagnostic process of other substance use disorders. It includes psychological evaluation and physical assessment. A healthcare provider may order some laboratory tests if necessary.

Anabolic steroid addiction affects a person by inducing extreme changes in their mood and behavior. The addict can be very aggressive, furious, and overreact. This can affect relationships.

5. Methamphetamine

Methamphetamine is a powerful nervous system stimulant. It’s among the most dangerous addictive substances. Methamphetamine addiction is a serious disorder wherein a person is physically and psychologically dependent on methamphetamine and keeps using the drug regardless of consequences and despite attempts to stop.

Numbers show that in 2020, 2.6 million people aged 12 and older used methamphetamine in the past year. Among people of the same age group, 1.5 million persons had methamphetamine addiction in the last 12 months. The same year, in 2020, around 23,837 deaths were associated with an overdose on meth.

Genetic and environmental factors interact with crucial developmental stages in a person’s life to contribute to the development of addiction. Peer pressure, past physical or sexual abuse and other types of trauma, early exposure to drugs, and family history all contribute to meth addiction. 

Effects of methamphetamine addiction include memory loss, aggression, mood swings, rotting teeth, extreme weight loss, hallucinations, paranoia, slower thinking, brain damage, and others.

Upon thorough physical and psychological evaluation, healthcare professionals also ensure a person meets the criteria from DSM-5 to establish the diagnosis. 

Methamphetamine addiction is difficult for any person because the drug is incredibly powerful. Besides severe appearance changes, a person experiences major mood problems that affect the way they interact with other people. Also, methamphetamine causes strong cravings and serious withdrawal symptoms when a person is not using the drug.

6. Inhalants

Inhalants are medical, industrial, or household products that produce strong vapors that people inhale to experience rush or high effects. Inhalant addiction is a type of SUD indicated by the continued use of inhalants and the development of various consequences because of it.

In 2020, around 2.4 million people aged 12 and older in the U.S. reported using inhalants within the last 12 months. Among people from the same age group, 215,000 were addicted to inhalants in the past year.

Causes that contribute to the development of addiction to inhalants include genetic predisposition, peer pressure, history of substance abuse, underlying mental health disorders, and exposure to inhalants through social media or social circles. 

The effects of inhalant use include drowsiness, disinhibition, agitation, and lightheadedness. Confusion and delirium occur due to exposure to high doses of inhalants. People who use inhalants are more likely to move on to other substances. In other words, addiction to inhalants could pave the way for other SUDs as well.

Diagnosis of inhalant use disorder includes criteria from DSM-5 as well as a thorough evaluation to uncover motivations behind the persistent need to keep using these substances.

While a person may experience a temporary rush or high with inhalants, negative effects are far worse. Besides health problems, addiction to inhalants can change a person’s social circle, negatively affect their education, and cause other problems whose consequences affect the overall quality of life.

7. Club drugs

Club drugs are drugs mainly used by adolescents and young adults at nightclubs, concerts, and bars to reduce inhibitions and heighten sensory perceptions. Addiction to club drugs is a disorder wherein a person experiences physical and psychological effects or changes when they stop taking the drugs.

While club drug addiction requires more research, in one study lifetime use of any club drug was up to 15% whereas ecstasy rates were around 14.8% and LSD at 14%.

The main cause of addiction to club drugs is the desire to enhance sociability and reduce inhibitions. A big role in the development of addiction belongs to changes in neurotransmitters in the brain. A person’s genetics, family history, and environment also play a role here.

Effects of club drug addiction include confusion, sleep deprivation, depression, paranoia, and anxiousness. Blood pressure and heart rate are also increased. 

Healthcare professionals usually diagnose club drug addiction when patients meet the criteria for SUD in DSM-5. Of course, the diagnostic process will also involve patient evaluation.

While many people take club drugs to become braver and experience the sense of “freedom” in clubs, addiction to these drugs can change the way the brain works. This causes significant changes in mood and behavior. Also, addiction to club drugs paves the way to legal troubles, risky activities such as driving under the influence, and professional difficulties. Many people lose their jobs because drug addiction impairs their performance at work.

Can drug addiction be cured?

Yes, drug addiction can be cured i.e. managed successfully with a well-structured treatment protocol. However, treatment isn’t a cure per se. Even though one in seven people in the United States is at risk of developing substance use disorder, only one in 10 will receive any form of treatment, according to a report by the surgeon general. 

The general public still has a long way to go in terms of changing their perception of drug addiction. This would further encourage persons with drug addiction to seek professional help. After all, treatments for substance use disorder are effective. 

For example, a paper from the Psychiatric Clinics of North America confirmed that many drug addiction treatment approaches are both effective and cost-effective. Proper treatment can decrease substance use and alleviate associated psychiatric, job, legal, family or social, and medical problems. Positive outcomes of drug addiction treatment are associated with treatment duration and retention.

How to treat drug addiction?

Drug addiction is treated with psychotherapy, support groups, and medications. For many types of addiction, a combination of different approaches yields the best results. The main goals of the treatment for drug addiction are to help patients stop using drugs, stay drug-free, become productive members of society or improve family dynamics and relationships.

According to the National Institute on Drug Abuse, the purpose of medications in drug addiction treatment is to suppress withdrawal symptoms during detoxification (the first stage of the treatment). Medications also reduce the risk of relapse or manage co-occurring disorders such as depression and anxiety. Managing these disorders can help treat addiction because mental health illnesses can worsen addictive behaviors.

The cornerstone of drug addiction treatment, however, is behavioral therapy. The main objectives of behavioral therapy include modifying attitudes and behaviors associated with drug use, increasing healthy life skills, and helping patients persist with other treatment approaches. 

Cognitive-behavioral therapy (CBT) is the most common psychotherapy approach in the treatment of drug addiction. This type of talk therapy teaches patients to identify negative thought patterns and behaviors in order to replace them with positive alternatives. After all, CBT is based on the fact that feelings and thoughts influence a person’s behavior. Changing them could help a person adopt healthier habits and coping mechanisms.

Besides CBT, drug addiction treatment may also include motivational interviewing to motivate patients to adopt positive changes, contingency management focusing on positive incentives to encourage drug abstinence, and multidimensional family therapy to improve family functioning and dynamics.

Treatment for drug addiction can be inpatient and outpatient. Inpatient or residential treatment offers a structured program for patients with moderate to severe addiction. The program involves living in a rehab center throughout the treatment. Outpatient treatment includes regular therapy sessions, but patients live at home and maintain employment during the program. This kind of treatment is useful for patients with mild to moderate addiction but also for those who have completed inpatient treatment.

Support groups are a valuable addition to any kind of treatment for patients with drug addiction. These groups gather people who are in the same situation. Participants receive encouragement to share their experiences, and both provide and receive support on their way to recovery and maintenance of sobriety.