Substance Abuse, Addiction, Tolerance, Dependence and Withdrawal
In order to understand drug use disorders such as opioid use disorder, it is important to distinguish between the terms abuse, addiction, tolerance, dependence and withdrawal. Unfortunately, many people, including some health professionals, often mistakenly use these terms interchangeably. However, the terms are not different names for the same phenomenon. Greater awareness of the differences between these terms can help us better comprehend the problems associated with drug use and the associated problems. This will enable us to create more effective, compassionate and humane treatments for this group of disorders.
Drug Abuse vs. Addiction
The biggest degree of confusion in defining these terms lies in the difference between abuse and addiction. Both of these difficulties result in a number social, psychological and physical problems for the individual. However, there are also some key differences. Substance abuse is defined as the use of a substance in a manner for which it is not intended and/or in amounts which are in excess of what is safe over a period of time. Some examples of abuse are using pain medication strictly to feel the euphoria and anxiety relieving qualities it provides or binge drinking to the point of blacking out to avoid thinking about something painful.
While abuse can lead to addiction, abuse is generally defined any use of illicit substances, or inappropriate use of legally prescribed medications such as taking larger doses than were prescribed. Someone abusing a substance can stop taking it, should they decide to do so, without significant withdrawal effects. The person suffering from drug abuse understands they shouldn’t be using the substance in the manner in which they are. Often, when the effects of the drug seem to be significantly impacting their life, or there is a serious consequence such as getting a DUI, they will stop taking it. [Note: The term “substance use disorder” was substituted for the term “drug abuse” in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5, 2013)].
Drug addiction is a more severe form of substance use which not only causes problems when the individual takes the drug but also when they attempt to stop taking it. According to NIDA, alcohol and drug addiction can be defined as a long term, relapsing brain disease characterized by regular drug seeking behavior and use, regardless of harmful consequences. The disorder involves uncontrollable cravings and maladaptive drug seeking behavior that takes up much of the individuals life.
NIDA refers to the disorder as a brain disease because drugs alter the functioning as well as the structure of the brain, often in long lasting ways. The alterations of the brain can result in changes in personality, social and occupational difficulties and other harmful behaviors observed in those who become addicted to drugs. Typically, the definition of addiction includes tolerance and dependence, though dependence may be physical, psychological or more commonly, both.
As previously mentioned, not everyone that uses drugs, legally or illegally, becomes addicted to them. There are different levels or stages of abuse and physiological and environmental influences that may cause an individual who is abusing drugs to continue taking them to the point they develop an addiction. Abuse always precedes addiction, and statistics show that many people who suffer from drug abuse do tend to go on to develop and addiction.
Dependence vs. Addiction
Dependence is another term commonly confused with the term addiction. Dependence simply means that the body has come to depend on an external source of a drug to prevent withdrawal from occurring. Most drugs create a pleasurable effect by increasing the level of certain substances in the brain.
While initially, the brain may be able to continue producing the naturally occurring substance over time, the brain senses it’s efforts aren’t needed as there is plenty of the substance circulating, and decreases or stops producing it. When a person then stops taking the drug without cutting down first, there is a period of time before the brain begins to generate the natural substance again, leading to negative physical and emotional symptoms.
Often, people will realize that they are becoming dependent on the substance or want to prevent dependence from occurring and will try to stop taking the drug on their own cold turkey. When someone is already dependent, they will experience the negative withdrawal symptoms associated with the substance. These symptoms may be physical, psychological or more usually, both.
The psychological symptoms can be emotional, such as depression or anxiety. They can also be cognitive, for example the person thinking that when they no longer uses the drug they won’t be as social, won’t be able to perform something at the same level, or they will just be too lethargic to do what they need to do day to day. They will then start taking the drug again to get rid of these symptoms and the quick abatement of the negative symptoms is such a relief that it reinforces taking the drug.
Dependence can occur without addiction. For example, someone with chronic pain may be able to take their opioid medication as prescribed developing tolerance over the long term, but don't develop the uncontrollable compulsion, loss of control and manipulative behavior aimed at getting more as tolerance develops.
Another example is prednisone, a synthetic steroid that is used to treat a number of inflammatory conditions. Prednisone doesn’t appear to produce addiction, however, if a patient stops taking it after several weeks, they will likely experience fatigue, weakness, body aches, and joint pain. Dependence is the desire to avoid withdrawal symptoms. While dependence is not addiction it can quickly become addiction. Many people who take a prescription medicine daily for a long time may become dependent.
Those who depend on drugs to function at a satisfactory level generally experience extreme psychological and physical discomfort when they do not use the drug for a long period. Feelings of dependency are persistent and compulsive, and without help and support, it is possible for people to experience these feelings for many years.
When substances such as morphine or cocaine are used repeatedly over time, tolerance can develop. Tolerance occurs when a person no longer responds to a substance in the way they originally did. Tolerance takes place at the cellular level. One way this can occur is the body increasing the speed with which the drug is metabolized such that it is removed from the body at a faster rate than previously.
The body can also adapt to the constant presence of a drug resulting in a decreased sensitivity of receptors, so more of the drug is needed to get the receptors to respond. When the sensitivity decreases, the person experiences less of an effect from the drug. The individual must then take more of the drug to obtain the same effect they first experienced.
This process explains why people with substance use disorders take more and more of a drug to get the sensation they desire. The development of tolerance does not automatically mean the person is addicted since it is possible for tolerance to occur without the cravings, drug-seeking and out-of-control behavior found in addiction. However, a number of drugs that produce tolerance are also addictive.
Tolerance doesn’t necessarily reduce the negative effects of the drug on the body. For example, over time a person can experience tolerance to alcohol, needing to drink more to feel the level of relaxation, decrease anxiety or avoid negative thoughts they did when they first began to drink. Even though they are feeling the same effect they once did, this does not mean their entire body is adapting to alcohol. The damage to their brain and liver will still increase with the increased alcohol consumption. The effects of drugs and alcohol on the body is not indicated by how the person feels regarding the desired effects.
Withdrawal is a group of physical and psychological symptoms that can range from mild to life-threatening depending on the substance used and the amount the person routinely takes. It occurs after the person has become dependent on the drug. This means that when the person stops taking the substance, they need to do it gradually to avoid withdrawal discomfort.
Withdrawal is one of the main factors that maintains addiction. When addiction first begins, often, the person is aware that there is a problem. However, attempts to stop taking the drug leads to such negative symptoms that the person begins to take the drug again to make the symptoms go away. Every time the person starts to contemplate no longer using the drug, the memory of the withdrawal symptoms make them anxious and they will likely come up with a reason that there is something happening that they need the drug to cope with. As time passes, the addiction grows worse and eventually they stop thinking about quitting.
The symptoms of substance withdrawal, and the length of the withdrawal, differ depending on the substance and the length of the addiction. For example, withdrawal from heroin and prescription pain medication results in flu like symptoms, dehydration, convulsions, hallucinations, insomnia, mood swings, Irritability, inability to concentrate, seizures, depression, anxiety, high blood pressure, paranoia, hyperactivity. These symptoms can last up to two weeks.
Withdrawal from cocaine on the other hand, results in depression, exhaustion, increased appetite, vivid, unpleasant dreams, muscle aches, nerve pain, anxiety, restlessness, chills, tremors, the inability to feel pleasure, mood swings and thoughts of suicide. These symptoms last for for seven to fourteen days.
Withdrawal from a substance after dependence has developed is best carried out in a substance abuse treatment facility that provided medical detox. Medical detox ensures that medical professionals are available to ensure the individual remains physically and emotionally safe by monitoring vital signs and psychological states. Physical stability involving safely removing the substance from the body is the first goal of detox after which psychological withdrawal symptoms can be addressed.
A Word About Recovery
Recovery is the process of reversing the brain changes that result from taking the drug and reacclimating to experiencing life without the effects of the substance. This is accomplished through a series of steps which need to be inpatient. It usually involves first getting the person safely off the medication followed by psychotherapy to deal with issues related to the reasons the person began taking the drug. An important goal is learning to function effectively without the substance and how to replace the addictive behaviors with healthy alternative behaviors. Coping skills training is generally incorporated to give the person new skills to address stressful life circumstances. Sometimes, medication may be used on a limited basis to help the person cope with physical withdrawal symptoms and extreme emotional symptoms such as anxiety while the person is learning to cope more adaptively. However, health care professionals are careful not to replace one addiction with another one.
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