Nature of dependence and withdrawal syndrome
The formation of pathological craving begins with repeated use of substances capable of causing euphoria—extremely pleasant subjective sensations. In individuals with a corresponding predisposition, the initial desire to simply repeat this experience transforms over time. The need shifts from controlled and desired to absolutely overwhelming.
A key concept in studying this phenomenon is withdrawal syndrome, or abstinence (the term originates from the Latin word abstinentia, meaning "abstinence"). This state develops at the moment when the supply of the habitual substance to the human body stops. Withdrawal syndrome is characterized by an extremely severe clinical course, in which the patient suffers not only from psychological discomfort, but also from pronounced somatic disorders, i.e., malfunctions in the work of various organs and systems. It is the fear of this distressing experience that often becomes the main motive for continuing drug use.
Classification of types of dependence
The division of drug dependence into various types is based on the specific nature of symptoms upon complete cessation of substance use.
1. Psychological dependence In this form, drug withdrawal does not cause severe physical (somatic) disorders. The clinical picture is limited to the psychoemotional sphere: the patient's mood drops sharply, deep emotional discomfort, a sense of motiveless fatigue, and pronounced depression occur. Typical agents causing predominantly psychological craving:
- Psychostimulants (amphetamine, cocaine);
- Hallucinogens (e.g., LSD);
- Cannabis products (hashish, marijuana);
- Nicotine.
2. Physical dependence This form proceeds significantly heavier, as emotional discomfort is combined with a full-blown withdrawal syndrome. The clinical picture includes both subjective complaints and objective physiological disorders that can be recorded upon examination. Typical substances forming physical dependence:
- Opioids (heroine, morphine);
- Hypnotics and sedatives (benzodiazepines, barbiturates);
- Ethyl alcohol (alcohol).
Dynamics of development and legal terminology
Drug dependence almost always goes hand in hand with tolerance (habituation). This means that the body's sensitivity to the administered agent gradually decreases. To achieve the initial effect of euphoria or simply relieve withdrawal, the patient requires a constant and steady increase in the dose. The maximum severity of the pathological process is observed when a person simultaneously presents with psychological dependence, physical dependence, and pronounced tolerance.
In medical and legal practice, it is important to distinguish between two related terms describing abuse:
- Substance abuse (toxicomania) is a broad, generalizing concept. It is used to denote the use of absolutely any substances for the purpose of obtaining an intoxicating effect.
- Drug addiction (narcomania) is a specific case of substance abuse with strict legal boundaries. Such a diagnosis is legitimate only if the substance abused by the patient is officially included in the state list of narcotic drugs and is subject to strict legal control.
Briefly: answers to topical questions
What is the pharmacodynamic mechanism of the development of tolerance to medicinal substances?
The pharmacodynamic mechanism of tolerance development consists in changes in the sensitivity or number of receptors, as well as in the depletion of necessary cofactors. The following main mechanisms are distinguished:
- Receptor desensitization — a decrease in receptor sensitivity to the drug (for example, during the use of $\beta$-adrenomimetics).
- Decrease in receptor density — a decrease in the number of receptors on the cell membrane.
- Depletion of cofactor reserve — a deficiency of thiol (SH) groups during the frequent use of organic nitrates, which leads to a decrease in the enzymatic production of nitric oxide and a decrease in therapeutic action.
What factors predispose a patient to the development of drug dependence?
Social, psychological, and biological factors predispose to the development of drug dependence. The following groups of conditions are distinguished:
- Social factors — low material level, stress, information overload, the influence of the social environment, and national customs.
- Psychological factors — low social adaptability and a weak type of higher nervous activity.
- Biological factors — hereditary predisposition to the use of psychoactive substances.
What clinical stages are distinguished in the process of drug dependence formation?
In the process of dependence formation, sources describe the stages of deviant behavior development and phases of tolerance changes.
Stages of dependence development:
- First stage ("Experimentation") — episodes are of a single and short-term nature, an attitude toward the behavior has not been formed.
- Second stage (stabilization and consolidation) — use becomes regular; normal needs are gradually suppressed, up to the possible suppression of basic physiological needs.
Phases of tolerance changes:
- Increase in tolerance — doses significantly exceeding the initial ones are required to achieve euphoria.
- Decrease in tolerance — against the background of organic damage to the brain and internal organs, the body loses the ability to resist intoxication, which increases the risk of severe poisoning.
Class and exam questions
What is abstinence?
Abstinence (from Latin *abstinentia* — abstinence) is a severe state that occurs upon cessation of substance intake, accompanied by mental and somatic disorders.
How does tolerance affect the course of dependence?
Tolerance leads to a decrease in receptor sensitivity, which is why a constant increase in the drug dose is required to achieve euphoria or relieve withdrawal syndrome.
Is any substance abuse called drug addiction?
No. Drug addiction is a legal diagnosis applicable only to those substances included in the official state list of narcotic drugs. The use of other intoxicating substances is called substance abuse (toxicomania).
What else to study on this topic
- Mechanisms of euphoria formation during psychostimulant intake
- Pathogenesis of somatic disorders in opioid withdrawal
- Factors of individual predisposition to dependence formation
- Receptor mechanisms of tolerance development
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