Addiction

In the previous post, I introduced the concept of addiction, simplifying it like this: the substances that can cause addiction have in common the activation of the reward circuit. Before moving into the clinical aspects, I think it’s useful to first familiarize ourselves with some important terms: tolerance, intoxication, withdrawal, and craving.

When substances are consumed regularly, they “trick” the reward circuit and a state of tolerance can develop. This means that the amount taken no longer produces the same effect, and increasingly larger amounts are needed to achieve the desired effect. The diagnostic manual (DSM-5) defines tolerance through the following two criteria:

• A need for significantly larger amounts to achieve the desired effect.
• A markedly diminished effect when using the same amount over time.

Intoxication refers to the appearance of typical symptoms for each substance, resulting from recent ingestion of that substance, and involves the emergence of significant problematic behavior. It is possible to become intoxicated with all the substances described in the diagnostic manual—except for tobacco. Additionally, the diagnostic criteria for intoxication specify that there is no better explanation for the symptoms.

If someone decides to stop (or drastically reduce) the use of the substance they are dependent on, withdrawal can occur. Withdrawal involves the manifestation of symptoms typical of the substance that caused the dependence in the first place. The DSM-5 defines withdrawal with the following three criteria:

• Cessation (or drastic reduction) of a substance that has been used heavily and over a long period.
• The appearance of typical withdrawal symptoms a few hours or several days after cessation (or drastic reduction).
• The substance is taken again to relieve or avoid withdrawal symptoms.

All the substances described in the DSM-5—except hallucinogens—can produce withdrawal. Additionally, the clinical framework for withdrawal specifies that symptoms cannot be better explained by another condition and that they significantly impair the individual’s functioning.

Craving is the persistent and pervasive desire to use the substance. It is an increasing urge that becomes uncontrollable, leading the person to give in to temptation and consume the substance. As one might imagine, craving often becomes especially strong when someone tries to abstain from the substance.

Sources:

• American Psychiatric Association (2013) – Diagnostic and Statistical Manual of Mental Disorders (5th ed.)
• Bernhill, J. W. (2014) – DSM-5 Clinical Cases

Recommended videos:

• https://www.youtube.com/watch?v=jZHtIb2ZMcA
• https://www.youtube.com/watch?v=0rehK3Mkyf4
• https://www.youtube.com/watch?v=kSgvhB23060
• https://www.youtube.com/watch?v=3tfRcpcMXMk
• https://www.youtube.com/watch?v=6rwsm6MXZ80

If you’d like me to describe another psychology topic in my own words, write it in the comments.