Drug addiction, also called substance use disorder, is a disease that affects a person’s brain and behavior and leads to an inability to control the use of a legal or illegal drug or medication. Substances such as alcohol, marijuana and nicotine also are considered drugs. When you’re addicted, you may continue using the drug despite the harm it causes.
Drug addiction can start with experimental use of a recreational drug in social situations, and, for some people, the drug use becomes more frequent. For others, particularly with opioids, drug addiction begins with exposure to prescribed medications, or receiving medications from a friend or relative who has been prescribed the medication.
The risk of addiction and how fast you become addicted varies by drug. Some drugs, such as opioid painkillers, have a higher risk and cause addiction more quickly than others.
As time passes, you may need larger doses of the drug to get high. Soon you may need the drug just to feel good. As your drug use increases, you may find that it’s increasingly difficult to go without the drug. Attempts to stop drug use may cause intense cravings and make you feel physically ill (withdrawal symptoms).
You may need help from your doctor, family, friends, support groups or an organized treatment program to overcome your drug addiction and stay drug-free.
Addiction vs. Abuse and Tolerance
Drug abuse is when you use legal or illegal substances in ways you shouldn’t. You might take more than the regular dose of pills or use someone else’s prescription. You may abuse drugs to feel good, ease stress, or avoid reality. But usually, you’re able to change your unhealthy habits or stop using altogether.
Addiction is when you can’t stop. Not when it puts your health in danger. Not when it causes financial, emotional, and other problems for you or your loved ones. That urge to get and use drugs can fill up every minute of the day, even if you want to quit.
Addiction also is different from physical dependence or tolerance. In cases of physical dependence, withdrawal symptoms happen when you suddenly stop a substance. Tolerance happens when a dose of a substance becomes less effective over time.
When you use opioids for pain for a long time, for example, you may develop tolerance and even physical dependence. This doesn’t mean you’re addicted. In general, when narcotics are used under proper medical supervision, addiction happens in only a small percentage of people.
Drug addiction symptoms or behaviors include, among others:
- Feeling that you have to use the drug regularly — daily or even several times a day
- Having intense urges for the drug that block out any other thoughts
- Over time, needing more of the drug to get the same effect
- Taking larger amounts of the drug over a longer period of time than you intended
- Making certain that you maintain a supply of the drug
- Spending money on the drug, even though you can’t afford it
- Not meeting obligations and work responsibilities, or cutting back on social or recreational activities because of drug use
- Continuing to use the drug, even though you know it’s causing problems in your life or causing you physical or psychological harm
- Doing things to get the drug that you normally wouldn’t do, such as stealing
- Driving or doing other risky activities when you’re under the influence of the drug
- Spending a good deal of time getting the drug, using the drug or recovering from the effects of the drug
- Failing in your attempts to stop using the drug
- Experiencing withdrawal symptoms when you attempt to stop taking the drug
Like many mental health disorders, several factors may contribute to development of drug addiction. The main factors are:
- Environment. Environmental factors, including your family’s beliefs and attitudes and exposure to a peer group that encourages drug use, seem to play a role in initial drug use.
- Genetics. Once you’ve started using a drug, the development into addiction may be influenced by inherited (genetic) traits, which may delay or speed up the disease progression.
People of any age, sex or economic status can become addicted to a drug. Certain factors can affect the likelihood and speed of developing an addiction:
- Family history of addiction. Drug addiction is more common in some families and likely involves genetic predisposition. If you have a blood relative, such as a parent or sibling, with alcohol or drug addiction, you’re at greater risk of developing a drug addiction.
- Mental health disorder. If you have a mental health disorder such as depression, attention-deficit/hyperactivity disorder (ADHD) or post-traumatic stress disorder, you’re more likely to become addicted to drugs. Using drugs can become a way of coping with painful feelings, such as anxiety, depression and loneliness, and can make these problems even worse.
- Peer pressure. Peer pressure is a strong factor in starting to use and misuse drugs, particularly for young people.
- Lack of family involvement. Difficult family situations or lack of a bond with your parents or siblings may increase the risk of addiction, as can a lack of parental supervision.
- Early use. Using drugs at an early age can cause changes in the developing brain and increase the likelihood of progressing to drug addiction.
- Taking a highly addictive drug. Some drugs, such as stimulants, cocaine or opioid painkillers, may result in faster development of addiction than other drugs. Smoking or injecting drugs can increase the potential for addiction. Taking drugs considered less addicting — so-called “light drugs” — can start you on a pathway of drug use and addiction.
Effect on Your Brain
Your brain is wired to make you want to repeat experiences that make you feel good. So you’re motivated to do them again and again.
The drugs that may be addictive target your brain’s reward system. They flood your brain with a chemical called dopamine. This triggers a feeling of intense pleasure. You keep taking the drug to chase that high.
Over time, your brain gets used to the extra dopamine. So you might need to take more of the drug to get the same good feeling. And other things you enjoyed, like food and hanging out with family, may give you less pleasure.
When you use drugs for a long time, it can cause changes in other brain chemical systems and circuits as well. They can hurt your:
- Ability to learn
Together, these brain changes can drive you to seek out and take drugs in ways that are beyond your control.
Drug use can have significant and damaging short-term and long-term effects. Taking some drugs can be particularly risky, especially if you take high doses or combine them with other drugs or alcohol. Here are some examples.
- Methamphetamine, opiates and cocaine are highly addictive and cause multiple short-term and long-term health consequences, including psychotic behavior, seizures or death due to overdose.
- GHB and flunitrazepam may cause sedation, confusion and memory loss. These so-called “date rape drugs” are known to impair the ability to resist unwanted contact and recollection of the event. At high doses, they can cause seizures, coma and death. The danger increases when these drugs are taken with alcohol.
- Ecstasy or molly (MDMA) can cause dehydration, electrolyte imbalance and complications that can include seizures. Long-term, MDMA can damage the brain.
- One particular danger of club drugs is that the liquid, pill or powder forms of these drugs available on the street often contain unknown substances that can be harmful, including other illegally manufactured or pharmaceutical drugs.
- Due to the toxic nature of inhalants, users may develop brain damage of different levels of severity.
Other life-changing complications
Dependence on drugs can create a number of dangerous and damaging complications, including:
- Getting a communicable disease. People who are addicted to a drug are more likely to get an infectious disease, such as HIV, either through unsafe sex or by sharing needles.
- Other health problems. Drug addiction can lead to a range of both short-term and long-term mental and physical health problems. These depend on what drug is taken.
- Accidents. People who are addicted to drugs are more likely to drive or do other dangerous activities while under the influence.
- Suicide. People who are addicted to drugs die by suicide more often than people who aren’t addicted.
- Family problems. Behavioral changes may cause marital or family conflict and custody issues.
- Work issues. Drug use can cause declining performance at work, absenteeism and eventual loss of employment.
- Problems at school. Drug use can negatively affect academic performance and motivation to excel in school.
- Legal issues. Legal problems are common for drug users and can stem from buying or possessing illegal drugs, stealing to support the drug addiction, driving while under the influence of drugs or alcohol, or disputes over child custody.
- Financial problems. Spending money to support drug use takes away money from other needs, could lead to debt, and can lead to illegal or unethical behaviors.
The best way to prevent an addiction to a drug is not to take the drug at all. If your doctor prescribes a drug with the potential for addiction, use care when taking the drug and follow the instructions provided by your doctor.
Doctors should prescribe these medications at safe doses and amounts and monitor their use so that you’re not given too great a dose or for too long a time. If you feel you need to take more than the prescribed dose of a medication, talk to your doctor.
Preventing drug misuse in children and teenagers
Take these steps to help prevent drug misuse in your children and teenagers:
- Communicate. Talk to your children about the risks of drug use and misuse.
- Listen. Be a good listener when your children talk about peer pressure, and be supportive of their efforts to resist it.
- Set a good example. Don’t misuse alcohol or addictive drugs. Children of parents who misuse drugs are at greater risk of drug addiction.
- Strengthen the bond. Work on your relationship with your children. A strong, stable bond between you and your child will reduce your child’s risk of using or misusing drugs.
Preventing a relapse
Once you’ve been addicted to a drug, you’re at high risk of falling back into a pattern of addiction. If you do start using the drug, it’s likely you’ll lose control over its use again — even if you’ve had treatment and you haven’t used the drug for some time.
- Stick with your treatment plan. Monitor your cravings. It may seem like you’ve recovered and you don’t need to keep taking steps to stay drug-free. But your chances of staying drug-free will be much higher if you continue seeing your therapist or counselor, going to support group meetings and taking prescribed medication.
- Avoid high-risk situations. Don’t go back to the neighborhood where you used to get your drugs. And stay away from your old drug crowd.
- Get help immediately if you use the drug again. If you start using the drug again, talk to your doctor, your mental health professional or someone else who can help you right away.
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