Hallucinogens

Main substances and mechanism of action

Key substances with pronounced hallucinogenic activity include lysergic acid diethylamide (LSD), mescaline, and psilocybin. A distinctive feature of this group of compounds is the complete absence of indications for use in official medicine.

The pathological impact on the central nervous system directly depends on the frequency and duration of use:

• Single use provokes a potent psychomimetic effect, which frequently escalates into acute psychotic states.
• Repeated use triggers pathophysiological mechanisms for the rapid development of psychological dependence, in which the patient completely loses control over the craving for the psychoactive substance.

Clinical picture of intoxication

The development of symptoms can be examined using the example of dimescaline, a potent and extremely rapid-acting psychoactive compound. The full clinical picture develops just a few minutes after the substance enters the bloodstream and is traditionally divided into two main categories.

Somatic manifestations:

• Pronounced tachycardia.
• Arterial hypertension.
• Hyperthermia (significant increase in body temperature).

Mental disorders:

• Abrupt, unpredictable mood swings.
• Complete disruption of the realism of perception of the surrounding world.
• True hallucinations.
• Synesthesia — a pathological mixing of senses in which stimulation of one analyzer evokes a response in another (e.g., the ability to "hear" colors).

Hallucinogen intoxication is associated with life-threatening complications. Patients frequently develop states of motiveless panic, tend toward antisocial actions (violence, senseless destruction of objects), and carry a high risk of suicide.

Polydrug addiction

Hallucinogens frequently become an element of polydrug addiction — a severe condition that develops with the simultaneous or alternating use of two or more narcotic drugs. The main motive for patients in such cases is the desire to achieve a specific complex of comfortable sensations that is fundamentally unattainable with monodrug addiction.

From the perspective of pathophysiology, the key feature of this condition is potentiation — the mutual enhancement of the toxic effects of all consumed drugs. This leads to catastrophic consequences for the body:

1. Rapid exacerbation of the degree of physical dependence.
2. Formation of an extremely severe and agonizing withdrawal syndrome.
3. Profound disorders in the functioning of all systems and organs.
4. A sharp decrease in the effectiveness of any therapeutic measures.

Dependence on non-narcotic substances

In addition to classical drugs, there are groups of psychoactive substances that are not legally classified in the corresponding schedules, but their systematic use causes severe pathologies. The main groups include:

• Ethanol.
• Psychostimulants (phenamine, meridil, caffeine).
• Household chemical products (volatile organic solvents, glues, insecticides).
• Psychotropic drugs and dissociative anesthetics.

Dissociative anesthetics

A prime representative is phencyclidine (a cyclohexylamine derivative), which is used in veterinary medicine for short-term immobilization of animals. In humans, it causes general psychomotor agitation, analgesia, dysarthria, and impaired motor coordination. In the mental sphere, disorganization of thinking, alienation from others, impaired perception of one's own body, and severe psychotic states are observed.

Medical psychotropic drugs

Legal medications used to treat psychoses, neurotic and neurosis-like disorders (to relieve fear, anxiety, and emotional tension) also possess pathological effects. These include:

• Antipsychotics (neuroleptics): chlorpromazine, chlorprothixene, haloperidol.
• Antidepressants: amitriptyline.
• Tranquilizers: medazepam, diazepam, bromdihydrochlorphenylbenzodiazepine.

Their uncontrolled use is capable of causing persistent psychological dependence, and with repeated use, physical dependence as well.

Briefly: answers to topical questions

Class and exam questions

What else to study on this topic

• Mechanisms of physical dependence formation during prolonged use of tranquilizers and antipsychotics.
• Pathogenesis of severe withdrawal syndrome against the background of polydrug addiction.
• Toxic effects of household chemical products (volatile solvents and insecticides) on the central nervous system.
• Comparative analysis of psychostimulant effects: amphetamine, methylphenidate, and caffeine.
• Features of phencyclidine use in veterinary medicine and the mechanisms of its dissociative action.

Other topics in «Chapter 18. Drug Addiction. Substance Abuse. Poisoning»

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