Drug Dependence

Definition and common characteristics of Drug Dependence

Drug dependence is that it is a condition resulting from the prolonged and usually intense consumption of a drug or drugs which has resulted in psychological and/or physiological dependence on drug consumption. This dependence causes significant problems in one or more areas of the person’s life.

A more specific and formal definition of drug dependence can be formulated using the Diagnostic and Statistical Manual, 4th Edition, of the American Psychiatric Association, (DSM-IV, 1994).

However the terms “drug abuse” and “drug dependence” are not used in the DSM-IV or the other widely used classification system, the International Statistical Classification of Diseases (ICD). Instead the terms “substance abuse” and “substance dependence” are used.

The term substance in the DSM-IV not only includes psychoactive chemicals of abuse but also medications and toxins with psychoactive effects and includes the following 11 classes of chemicals: “alcohol, amphetamine or similarly acting sympathomimetics; cannabis; cocaine; hallucinogens; inhalants; nicotine; opioids; phencyclidine or similarly acting arylcyclohexylamines; and sedatives, hypnotics, and anxiolytics”.

Using the DSM-IV criteria for substance dependence but applying it to the case where the substance is one of the illicit drugs described above, the diagnosis of drug dependence is made when one or more of the following occurs over one year:

  • Tolerance which is defined by increased amounts of substance to achieve same degree of intoxication
  • Withdrawal which is defined by a set of symptoms characteristic of the specific substance alcohol or drug of abuse.
  • Substance is taken in greater amounts or over longer time periods than intended
  • There is a persistent desire and or attempts to reduce or stop substance use but these are not successful.
  • A great deal of time is spent making sure of the availability of substance, consuming substance, or recovering from the negative consequences of substance use; example the hangover.
  • Important social, occupational, or recreational activities are diminished or given up completely because of substance dependence.
  • Substance use continues despite awareness of causing persistent physical or psychological problems which have either been caused by or intensified by taking the substance.

Drug abuse differs from drug dependence

Research has shown important differences between alcohol abuse and alcohol dependence (Hartford and Muthen, 2001) and it reasonable to conclude that the same distinction between drug abuse and drug dependence.

For example in drug abuse there is no significant psychological or physiological dependence whereas drug dependence and associated symptoms e.g. withdrawal symptoms, craving etc are characteristic of drug dependence. Also because of these differences in the nature of drug abuse and drug dependence, there are critical differences between the treatments of these two distinct conditions.

Prevalence of drug dependence

The lifetime prevalence for drug dependence was found to be 3.0% in a large epidemiological study carried out recently in the United States (Kessler et al, 2005). This makes it a little less than half the lifetime prevalence of drug abuse which was found to be 7.9% in this same study. It is to be noted that for both alcohol and drugs, dependence is less than half as common as abuse.

Alcohol dependence and codependence (developmental trauma)

The presence of an addiction of some kind has long been held as a main secondary symptom of codependency. Other names for codependency are developmental trauma and complex PTSD.

There is indeed a lot of evidence that many individuals who abuse or become dependent to any substance be it alcohol or illicit drugs have often been exposed to previous trauma during their childhood or thereafter.

For example, a study of borderline personality disorder, a severe form of what many call codependence, in patients with recent deliberate self-harm in Hong Kong, found they were more likely to suffer from a current alcohol and substance use disorder Wong (2010).

Also, research by Boriskin (2008) found that 25 to 50 percent of clients with a substance use disorder also meet the conditions for a diagnosis of post traumatic stress disorder (PTSD).

Hence there is strong reason to conclude that a person who experienced repeated or prolonged trauma during their childhood (and hence is likely codependent) is at greater risk of developing drug/alcohol abuse or dependence in adulthood.

Treatments available for drug dependence

Fortunately there are a number of effective treatments for drug dependence as listed below:

  • Psychotherapy: individual or group. Many psychotherapeutic modalities e.g. cognitive behavioural therapy are used to treat drug dependence with varying degrees of success.

    It likely is the case that individual psychotherapy can be very useful but only if there is a strong additional component of group psychotherapy or attendance at a self-help group such as Narcotics Anonymous. A limitation of individual psychotherapy is its cost,  particularly in the case of addictions where extended treatment with a maintenance component is generally necessary.
  • Self-help groups such as Narcotics Anonymous are effective as demonstrated by the fact that they have existed for decades and many recovered through them. There is no evidence that self-help groups are less effective than formal treatment by a mental health worker.

    Prochaska and his colleagues have shown there are five stages which people progress through to recover from an addiction: pre-contemplation, contemplation, preparation, action and maintenance.

    The final stage is maintenance because relapse is the main problem in recovery from drug (substance) dependence. Maintenance activity may be required for years, perhaps for the rest of the recovered person’s life. Very few individuals can afford long term psychotherapy but the maintenance stage can be provided by weekly attendance at NA meetings for extended periods of time.
  • Medications: There is increasing use of medications to reduce withdrawal symptoms and to prevent illicit drug use. As in alcoholism, but perhaps even to a greater degree, relapse is the main problem in recovery from drug (substance) abuse.

    Although withdrawal is dealt with relatively easily and detoxification can be obtained, the person addicted to illicit drugs tends to relapse, making long term abstinence for the drug the most difficult objective of treatment to attain.

    Methadone is a synthetic narcotic used in treatment of heroin addicts because it relieves withdrawal without producing a strong euphoria. Heroin antagonists prevent addicts form experiencing a high when heroin is taken. Drugs are now being sought which will alleviate the withdrawal symptoms of cocaine.
  • Detoxification facilities where the drug dependent person can withdraw under medical care e.g. vigilance of seizures and appropriate medical intervention including anti-seizure medications.
  • Rehabilitation and self-help residential homes have proved useful and involve a total drug-free environment, charismatic role-models, direct confrontation in group therapy, and separate the drug dependent person from previous social contacts with other drug users.
  • A factor that makes treatment especially important for drug addicts is the risk of acquiring HIV infection since the virus can be transmitted through the needles that addicts share with one another. Since the addict may be married there is the risk of transmission the spouse. This has resulted in increased attention to reaching out to those dependent on opiates and in some countries to the provision of free sterile needles to reduce HIV transmission.
  • Prevention is considered the best way to deal with drug dependence. Psychoeducation is the most important tool in preventing the development of drug dependence. Since generally the introduction to drug use starts in teenage years or even earlier, it is best to start drug education in school as soon as possible but at an age appropriate level.


Boriskin, J. A. (2008, March). Effective treatments of complex PTSD and addiction. Paper presented at the meeting of Addiction, Trauma, and Co-Occurring Disorders, San Diego.

Harford, T. C., & Muthen, B. O. (2001). The dimensionality of alcohol abuse and dependence: A multivariate analysis of DSM-IV symptom items in the National Longitudinal Survey of Youth. Journal of Studies on Alcohol, 62, 150–157.

Wong, Hiu-Mei; Leung, Henry Chi-Ming; Chow, Lai-Yin; Kam, Wai-Kwo & Tang, Alan Ka-Lam. (2010) Prevalence of borderline personality disorder and its clinical correlates in Chinese patients with recent deliberate self-harm. Journal of Personality Disorders, 24(6), 800-811.