Addiction vs. Dependence: Understanding the Difference

Psychological vs. Physiological Aspects

It’s possible to have addiction without dependence,⁵ and vice versa. But if you have both, your physical and psychological symptoms might feed off each other. For example, you might start taking opioids to relieve pain after an injury. Then, as your body heals, lowering your dosage could make you feel anxious. What starts as a physical need can become an emotional one.

Without proper support, this can quickly lead to addiction. When you’re ready to recover, it may help to differentiate between the physiological and psychological aspects of what you’re going through. Doing this empowers you and your care team to choose the most effective types of treatment.

Psychological Aspects of Addiction

There’s a good reason addiction feels so out of your control. Addictive substances change the way your brain works.⁶ They flood your brain with dopamine, a feel-good chemical that activates your reward system. Over time, substances change the way your brain produces dopamine.⁷ Drug use might become the only thing that gives you a sense of reward. The National Institute on Drug Abuse explains:

“The difference between normal rewards and drug rewards can be likened to the difference between someone whispering into your ear and someone shouting into a microphone. Just as we turn down the volume on a radio that is too loud, the brain of someone who misuses drugs adjusts by producing fewer neurotransmitters in the reward circuit, or by reducing the number of receptors that can receive signals. As a result, the person’s ability to experience pleasure from naturally rewarding (i.e., reinforcing) activities is also reduced.”

Physiological Aspects of Dependence

Like your brain, your body can quickly get used to any drugs⁸ you take. If you use a drug often, you’ll need higher doses to feel the same effects. This is called tolerance. You can develop a tolerance to some drugs very quickly. For example, it takes just 2-3 doses of opioids⁹ for some people to develop a tolerance.

Once you have a tolerance, you might start taking higher doses to get the same effect. You might also become physically dependent on the drug, and feel withdrawal symptoms if you try to quit. Many people keep using drugs to avoid those withdrawal symptoms. If this pattern continues, it might lead to addiction. 

If your body depends on a substance, withdrawal can range from being uncomfortable to dangerous. Detoxing from certain substances—like alcohol, opioids, and benzodiazepines—can even be fatal. Formal addiction treatment can keep you safe during this phase of recovery.

Implications and Consequences

Addiction can impact every aspect of your life, starting with your mental health.¹⁰ Substances change your brain, and might contribute to co-occurring disorders like anxiety and depression. These symptoms, along with other aspects of addiction, can interfere with your relationships. If you prioritize drug use over your colleagues or loved ones, you might face serious consequences. 

Dependence also affects your physical health, whether or not you have an addiction. For example, alcohol dependence can lead to liver problems,¹¹ heart disease, and even cancer. Opioids increase your risk for cardiac and respiratory problems.¹² And illicit drug use has a high risk of overdose¹³ and death.

While addiction and dependence aren’t the same, they often overlap. So when you start recovery, both your body and mind will need time to heal.

Connect with a rehab program for alcohol and drug addiction to determine which treatments can best meet your unique needs.

Frequently Asked Questions About Addiction vs Dependence