The Difference Between Addiction and Physical Dependence

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child addicted to pills

Addiction is a frightening word. Some people who live with chronic pain worry that if they take too many opioid pain killers, they may become addicted to them, as do people who take certain types of medications for mental illnesses, such as depression or anxiety. It’s an understandable concern, given the news of the increasing abuse of prescription medication among people from all walks of life. But it’s important to understand there’s a difference between an addiction and physical dependence on a drug and to recognize how each affects the body differently, so you can work with your doctor to find the most effective treatment.

How do potentially addictive medications work?

Opioids may be taken many ways, such as by mouth (pills and liquids), injection, intravenous (IV), or through patches placed on the skin. They are also available in immediate or short-acting formulations or long-acting ones. Short-acting opioids begin working soon after they’ve been administered. Long-acting ones provide a slow, steady release of the medication, rather than giving it to you all at once. No matter which way these drugs are taken or administered, they relieve pain by altering your brain’s perception of the pain messages. In effect, telling your brain that the pain doesn’t exist. Antianxiety and antidepressant medications also work in the brain, by altering neurotransmitter levels or the chemical messages that process pain.

What is physical dependence on a drug?

Imagine you’re taking morphine for pain and it’s working fairly well but after a while, you notice your pain relief isn’t as effective as it has been. You are given a stronger prescription and this works for a while until your body gets used to it again, and the cycle is repeated or the medication is changed. This is your brain adapting to the drug in your system, and becoming dependent on it over time. If you suddenly stop taking the morphine, you may feel physically uncomfortable as your body gets used to not having the drug in your system anymore. To reduce the risk of the discomfort, your doctor likely would recommend you wean off it, lowering the dose slowly over time.

But physical dependence isn’t restricted to opioids, like morphine. A very common physical dependence is one that affects millions of Americans: coffee. People will say they are addicted to the caffeine in their morning cup of coffee, but in reality, they are dependent on it. When they stop consuming coffee, they may develop physical symptoms, such as headaches, anxiety, lack of concentration and more. However, if they wean themselves off the coffee, symptoms are less likely to appear or become less severe. This same phenomenon is true for chronic corticosteroid use, barbiturates, and nicotine.

How is an addiction different from physical dependence?

According to the National Institute on Drug Abuse, addiction is a chronic, relapsing brain disease. People who are addicted to a medication get more out of the drug’s action than what it’s meant to provide. Instead of simple pain relief, for example, the person may experience a feeling of euphoria when taking the drug. In other words, addiction relates to behavioral issues which compel the individual to seek the drug, whereas physical dependence describes the symptoms which arise when consumption of the abused substance is discontinued. Certainly these two problems go hand-in-hand. Addicts develop not only a physical dependence on a medication, but a psychological dependence: They need to have the drug, they must have it, and they will do just about anything to get it, possibly displaying compulsive destructive behavior in order to do so, such as:

  • Lying

  • Stealing

  • Spending money budgeted for home, food, and other essentials

  • Visiting more than one doctor to get multiple prescriptions

  • Buying drugs on the street

 When they don’t have the drug in their system, they may first experience reactions such as:

  • Agitation
  • Anxiety

 The longer they go without the drug, they may experience:

How are physical dependence and addiction treated?

In most cases, physical dependence on a drug is managed by slowly weaning you off the medication, lowering the dosage, and giving your body time to adapt. Addiction requires a different approach because addiction is a disease. It may be treated by substituting the drug with a less harmful medication, as well as with treatment counseling, which could take the form of psychotherapy, 12-step programs, or in-patient rehabilitation. 

Do I need to worry about addiction if I take pain killers or other strong medications?

While anyone could develop an addiction, some people do have a higher risk than others. Talk to your doctor about your risk for addiction if you have:

  • Previous substance abuse issues, such as drinking too much alcohol

  • A history of trauma or abuse

  • Previous or current mental health conditions

  • A family history of addiction or substance abuse problems 

Prescription medications, particularly those for pain and mental health, have significantly changed lives. They’ve allowed people to continue working, care for their families, and live a better quality of life. However, if you are worried about developing a physical dependence or addiction, don’t be afraid to talk to your prescribing doctor about your concerns. The earlier you identify your risk, the better. Your provider can take steps to find appropriate treatment and, when possible, offer alternative therapies for your underlying condition.

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2021 Jan 1
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.

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