Addiction FAQs

Edmund Murphy
Dr. Samantha Miller
Written by Edmund Murphy on 25 August 2021
Medically reviewed by Dr. Samantha Miller on 17 December 2023

Below are some of the most frequently asked questions we receive about then ins and outs of substance and behavioral addictions.

What causes addiction?

No one thing leads to addiction, however, there are several factors that increase the risk of developing addiction, such as:

  • Genetics
  • Environment
  • Socioeconomics
  • Personal trauma
  • Psychological factors

Can drug and alcohol abuse lead to mental health issues?

It’s not uncommon for a person with a drug or alcohol addiction to have another mental illness. However, scientists say it’s difficult to know whether addiction is a cause of mental illness or whether people with a mental health disorder are more likely to turn to drugs or alcohol and develop an addiction. It’s also likely that some of the same genes and brain regions involved in addiction are also involved in other mental health disorders, such as schizophrenia and depression. People with mental health issues and addictions are often treated for co-occurring disorders.

How long do drugs and alcohol stay in your system?

Drugs and alcohol are typically detectable in the blood or urine drug tests for a period of hours to weeks. However, several factors affect the detection rate of substances in urine and blood. These include the type of test used, the dose taken, the user’s tolerance level, the potency of the substance, the metabolism of the user, and the existence of any underlying medical conditions. In addition, it is possible to detect some substances in other body tissues such as hair for months. 

Click here to see the average length of time a substance will stay in the blood and urine.

Is marijuana addictive?

When a person uses marijuana, the tetrahydrocannabinol (THC) component activates cannabinoid receptors in the brain via a neurotransmitter called anandamide. This leads to the activation of reward and pleasure pathways in the brain. As a result, using marijuana regularly can lead to dependence on the drug, requiring it to feel good or even normal. Find out more about marijuana addiction here.

How much do drugs cost?

The cost of drugs, be they prescription painkillers or an illegal drug like meth, can vary significantly from location to location. What doesn’t change is the cost drug abuse can have on a person's way of life. If you feel you are suffering from drug abuse, contact a rehab center today.

Click here for more information on the cost of addiction in America.

Are opiates the same as heroin?

“Opiates” is the given term for any controlled substance derived from opium, a naturally occurring chemical found in poppy seeds. These controlled substances, or drugs, are often clinically prescribed for those suffering from mild to severe pain, hence also being referred to as opioid painkillers. Due to their calming effects and pain relief, opioid painkillers become highly addictive if abused. 

Illicit substances such as heroin are also classed as opioids as they come from the same origin. They have the same effect on the abuser but are acquired via different channels, though both have the same high potential for addiction.

People who abuse opiate painkillers to the point of dependence will often begin to form cravings after a period of not taking them. This can lead to destructive behaviors, such as lying to doctors to get prescription drugs, as well as to friends and family about the level of their opiate abuse. 

Some abusers of opioid prescription painkillers may turn to heroin if they can no longer obtain prescription pills. The effects of taking heroin provide the closest feeling to opiate painkillers and are just as addictive and dangerous.

Is fentanyl dangerous?

Fentanyl is a powerful opioid pain medication similar to morphine, codeine, oxycodone, and methadone. Fentanyl is most often prescribed as a slow-release patch to people with long-term, severe pain. When used in this way, it can be very effective and safe.

Fentanyl is more potent than most other opioids - up to 100 times stronger than morphine - and is very dangerous if misused. Even a tiny amount can result in overdose and death.

In recent years, there have been increasing amounts of fentanyl-related overdoses. This is partly due to drug dealers cutting substances such as cocaine and heroin with fentanyl to produce a high with fewer narcotics. Fentanyl can be impossible to trace when cut with other substances and is incredibly dangerous. Access to the opioid overdose-countering drug Naloxone as well as the ready availability of fentanyl test strips are leading the way in reducing fentanyl-related overdoses.

What are the most common addictions?

Almost all substance abuse can form a drug addiction, though some substances are more addictive than others. This may be due to their mechanism of action, availability, cost, and the user’s own background and risk factors. The most common form of addiction in the United States is tobacco (nicotine), with over 40 million people addicted. 

Click here for the full list of the ten most prevalent addictions in the United States today.

What is the difference between addiction and dependence?

A dependence presents itself when someone builds up a physical tolerance to a substance, meaning they may have withdrawal symptoms if they stop using the drug. Dependency can usually be resolved by slowly weaning off the drug and changing behavior patterns. 

On the other hand, addiction occurs when a person's brain chemistry has changed from prolonged or extensive substance abuse. Both drug addiction and behavioral addiction cause uncontrollable cravings, which the user will strive to fulfill despite the negative impact on their life. Often, the only way an addicted person can get help is through professional substance abuse treatment.

Read more about addiction vs dependence here.

Was this page helpful?

Your feedback allows us to continually improve our information

Activity History - Last updated: 17 December 2023, Published date:


Dr. Samantha Miller is a practicing NHS doctor based in Glasgow, UK, who regularly contributes as a medical reviewer for mental health and addiction.

Activity History - Medically Reviewed on 27 July 2021 and last checked on 17 December 2023

Medically reviewed by
Dr. Samantha Miller


Dr. Samantha Miller


Ready to talk about treatment? Call us today. (855) 648-7288
Helpline Information
Phone numbers listed within our directory for individual providers will connect directly to that provider.
Any calls to numbers marked with (I) symbols will be routed through a trusted partner, more details can be found by visiting
For any specific questions please email us at

More on addiction