What are PAS and dependence
According to the WHO definition, psychoactive substances (PAS) are products of various chemical structures capable of altering mental state, causing euphoria and pathological craving. These include both illegal substances (opium, cocaine) and everyday ones (alcohol, tobacco, coffee, household chemicals).
In Russia, diagnoses depend on the legal status of the substance:
- Drug addiction (Narkomaniya) — dependence on a substance legally recognized as a narcotic.
- Toxicomania — dependence on a PAS not included in the narcotic list (e.g., glue or certain medications).
Abroad, these terms are not used. The concepts of substance abuse and addiction (including non-chemical forms) are more commonly used.
How attitudes toward dependence changed
Throughout history, views on the nature of dependence have transformed significantly:
- Bad habit or lack of upbringing.
- Symptom of another disease (e.g., schizophrenia or neurosis — Z. Freud's psychoanalytic approach).
- Independent disorder with characteristic symptoms. In Russia and Europe, this approach became established earlier than in the USA (works of S.S. Korsakoff, E. Kraepelin, V.M. Bekhterev).
- Conditioned reflex theory — dependence as a result of pathological learning (based on the works of I.P. Pavlov).
- Social disease — a consequence of the influence of environment and culture.
- Multilevel polyetiological disorder — a modern view that takes into account the biological substrate (dopamine system, opiate receptors, genetics).
Clinical signs of dependence
Regardless of the type of PAS, the development of dependence is accompanied by general clinical manifestations:
- Psychological dependence: pathological craving for the substance, constant search for PAS, obsessive thoughts about its intake. Craving can be primary (outside of intoxication) and secondary (occurring when use is resumed).
- Physical dependence: development of withdrawal syndrome (abstinence syndrome) — a complex of somatovegetative and neurological disorders upon cessation of PAS.
- Tolerance change: the need to increase or decrease the dose, failure of the body's protective reactions.
- Personality changes: anosognosia (denial of illness), loss of moral control, degradation.
- Consequences: toxic damage to organs (liver, central nervous system, heart) and social maladaptation.
Briefly: answers to topical questions
What clinical manifestations are characteristic of opioid withdrawal syndrome?
Opioid withdrawal syndrome develops 8–16 hours after the last use and manifests with symptoms in a specific order of appearance.
- Initial manifestations — anxiety, restlessness
- Autonomic disturbances — rhinorrhea, lacrimation, sneezing, hyperhidrosis, chills, tachycardia, hypertension, peripheral cyanosis, mydriasis
- Sleep disorders — persistent insomnia
- Pain syndrome («withdrawal pain») — pain in the lower back, spine, lower extremities
- Gastrointestinal disorders (after 1–2 days) — vomiting, spasmodic abdominal pain, diarrhea with tenesmus
Maximum severity is reached by days 3–4, acute manifestations subside by days 7–10.
Which neurotransmitter systems form the biological substrate of dependence?
The biological basis of dependence is associated with specific neurotransmitter mechanisms.
- Dopamine system — belongs to the key mechanisms of dependence formation; the euphoriant effect of alcohol is realized through brain «reward systems», where dopamine and neuropeptides act as the main mediators.
- Opiate receptors / opioid system — belong to the key mechanisms of dependence formation; the action of various euphoriant substances, including drugs, tobacco, and alcohol, is ultimately realized through the activation of the opioid system.
For alcoholism and alcoholic psychoses, a neurotransmitter system imbalance against the background of alcohol withdrawal is also described: insufficient activity of inhibitory systems, primarily GABA and aspartate, and excessive activity of glutamate and dopamine against the background of acetylcholine deficiency.
What stages of development are distinguished in chronic alcoholism?
Sources indicate the following clinical signs of the stages of alcoholism.
- Stage I — loss of quantitative control over the amount drunk.
- Stage II — the appearance of pseudodipsia (pseudospoes) and the formation of physical dependence. Tolerance reaches a maximum and remains unchanged for a long time — the «tolerance plateau». Alcoholic withdrawal syndrome is characteristic: anorexia, insomnia, pronounced tremor, impaired concentration, internal restlessness, inability to work. Personality changes are described: loss of a sense of shame, lightheartedness, promiscuity in acquaintances, antisocial behavior for the sake of alcohol. Somatic complications are possible: fatty liver disease, hypertension, acute pancreatitis, hemorrhoidal bleeding or thrombosis of hemorrhoids, arrhythmias.
Distinguishing drug addiction from toxicomania is easy: if the substance is in the official legal list, it is drug addiction; if not, it is toxicomania.
Class and exam questions
What is the essence of the degeneration concept?
This is a historical theory (B. Morel) according to which mental illnesses and behavioral disorders are caused by the accumulation of «bad qualities» in offspring.
How does genetics influence the risk of developing alcoholism?
The risk is significantly higher if there are dependent relatives. For example, in women suffering from alcoholism, fathers also had this dependence in 77% of cases.
What else to study on this topic
- The contribution of domestic psychiatrists to addictology (Kantorovich, Strelchuk, Zislin)
- Biochemical mechanisms of dependence formation
- Detailed statistics of visits and the structure of substances used in the Russian Federation
- Differences between primary and secondary pathological craving
Master the entire topic in the "Psychiatry" course
This is a summary. The course covers everything tested in classes and exams.
- Complete study guide on «Basics of Addictology» and 499 more pages of the subject
- Assignments and quizzes after every topic — just like in a colloquium
- AI tutor answers questions on the topic anytime
- 7 video lessons on the subject
Other topics in «Chapter 21. Disorders due to use of alcohol and other psychoactive substances»
Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.