Plenty of people say the same thing in the first conversation. I am not an addict, my body just got used to it. Sometimes that is accurate. Dependence and addiction overlap, and they get used as if they were the same word, but they are two different things and the difference changes what treatment has to do.

What is drug dependence?

Dependence is physical. Use a drug often enough and the body adapts to it. The clearest sign is withdrawal when the drug stops.

Dependence directly impacts the brain, including the thalamus and brain stem. The brain and body only function normally when the drug is present because the drug has disrupted the brain’s chemical balance. Over time, chemical production is altered to build a tolerance to the drug. That tolerance can shift to dependence, messing with a person’s chemical balance when they stop taking the drug.

Mental dependence

Mental dependence is a type of substance dependence characterized by triggers. Biochemical changes can occur in the brain when a trigger is present, and those chemicals influence behavior. Common triggers include emotional responses, enablers, certain places, or things associated with a drug.

Physical dependence

Dependence usually means physical dependence. Tolerance builds, and withdrawal symptoms come when the drug is not there. The body reacts to the absence, which makes it easy to spot.

Withdrawal

Withdrawal is what happens in detox. Cut back or stop, and the body and the mind both react. Symptoms run from mild to severe, and some of them are fatal. They vary by person and by substance, which is why withdrawal should be handled with medical treatment.

What is drug addiction?

Using a substance over and over does not always end in addiction. Addiction is a compulsion, and you see it in behavior. The substance comes first, whatever it costs the person taking it. Thinking turns irrational when the substance is not there. The reliance is mental as much as physical.

Substance use disorder

The medical term is now substance use disorder, classified as mild, moderate or severe. The wording changed to take some of the stigma out of the word addiction, and to cover more of the people it applies to. The hope is that more people ask for help when the label is less loaded.

Is there a difference between drug dependence and addiction?

You can be dependent on a substance without being addicted to it. Someone who drinks heavily for days in a row adapts to the alcohol, and when they stop they may get withdrawal symptoms, but they are not necessarily addicted. However, if that person is unable to stop drinking, they may have an alcohol addiction.

A high tolerance and a growing dependency are both warning signs for addiction. Illicit drugs and prescription medication can both cause dependency and withdrawal. Addiction is when someone keeps seeking a substance out after the consequences have shown up, and those consequences are usually visible: a lost job, trouble at home, trouble with the police.

Is the difference important?

The right word points to the right treatment. Dependence is treated by getting someone through withdrawal and the cravings that follow it. Addiction needs that plus the mental work, because the pull toward the substance stays after detox is over. Relapse is part of the picture.

What is tolerance?

With repeated use over time, a person’s response to a drug is diminished. Developing a tolerance to prescription or illicit drugs requires more of the drug to achieve the same effect. Tolerance does not necessarily lead to an addiction, however it can be part of the early stages of addiction.

The three types of drug tolerance include:

• acute tolerance
• chronic tolerance
• learned tolerance.

Acute tolerance

Acute tolerance is characterized by tolerance built in a short period of time. Repeated use of a drug can lead to short-term tolerance. For example, cocaine results in acute tolerance because the high experienced from the first dose is usually felt more than the high from a subsequent dose in a short period.

Chronic tolerance

Chronic tolerance occurs when a substance is regularly misused over a long period of time. The prolonged exposure can occur over weeks or months and causes the body to adapt to the drug. For example, a chronic tolerance can be developed for prescription opioids. People who misuse opioids often have to increase the dosage or change the method of using the drug to achieve a similar euphoric effect.

Learned tolerance

Learned tolerance can occur when someone does not appear intoxicated because they have learned to conceal the effects of drugs. For example, people who drink heavily may not seem drunk. By practicing tasks under the influence of alcohol, they are able to compensate for the effects of drinking.

What factors impact the severity of dependence?

The longer someone uses an addictive substance, the worse the dependence gets. How they use it matters as well. Injecting or snorting a drug puts it into the brain faster than swallowing or drinking it, so dependence and addiction can take hold in less time.

The drug itself matters too. Crystal meth and cocaine build dependency fast, partly because people raise the dose with each bender. While tolerance for alcohol or benzos can build quickly, dependency on these substances typically takes longer to form.

Can you tell whether you are dependent or addicted?

Dependence is easy enough to spot. Stop the drug, and if withdrawal symptoms arrive, the dependence is there. Addiction is harder to call from the inside, and being unsure which one you have is one more reason people put off asking for help.

A doctor can settle it. An exam shows whether dependence or withdrawal is present, and a mental health evaluation covers the rest. If you are worried either way, speak to a medical professional now. You do not have to be certain first.

Dependence has treatment options, including inpatient drug detox programs. Medical staff can ease withdrawal symptoms and keep someone comfortable while the body clears the drug. With addiction, detox is only the first step. The counseling and support that follow are where the reasons behind the use get worked on, and that is what keeps someone from going back to it.