Tranquilizers are medications designed to calm the nervous system and reduce mental distress. They alleviate feelings of anxiety, fear, tension, and agitation. These drugs work by influencing brain activity to promote a more relaxed state, helping individuals manage symptoms that can interfere with daily life.
Categories of Tranquilizers
Tranquilizers are broadly categorized into two main groups: major and minor. Major tranquilizers, also known as antipsychotic agents or neuroleptics, address severe mental disturbances like schizophrenia, managing delusions and hallucinations. Minor tranquilizers, or anxiolytics, are prescribed for milder anxiety and tension.
Within the minor tranquilizer category, common types include benzodiazepines and non-benzodiazepines (Z-drugs). Older sedative drugs, such as barbiturates, are also tranquilizers, though their use has largely been superseded by safer alternatives. While major tranquilizers primarily act by blocking dopamine receptors, minor tranquilizers exert their effects through a different pathway, focusing on an inhibitory neurotransmitter.
Brain Chemistry and Action
The calming effects of minor tranquilizers, like benzodiazepines and non-benzodiazepines, stem from their interaction with gamma-aminobutyric acid (GABA). GABA is the primary inhibitory neurotransmitter in the central nervous system, reducing nerve cell excitability. Tranquilizers enhance GABA’s natural activity, decreasing overall brain activity.
This enhancement occurs primarily at GABA-A receptors, specialized proteins on neuron surfaces. When GABA binds to these receptors, it opens a channel allowing negatively charged chloride ions to flow into the neuron. This influx makes the neuron more negatively charged (hyperpolarization), making it less likely to fire an electrical impulse. Benzodiazepines bind to a distinct site on the GABA-A receptor, increasing the frequency of chloride channel opening when GABA is present.
Non-benzodiazepines, while chemically different, share a similar mechanism by enhancing GABA’s effects at the GABA-A receptor. These drugs often show a preference for specific subtypes of the GABA-A receptor, particularly those linked to sedative properties. Barbiturates, on the other hand, prolong the duration for which the chloride channel remains open, leading to a greater influx of chloride ions and a more profound inhibitory effect.
Physical and Mental Effects
When a tranquilizer takes effect, individuals experience physical and mental changes. Sedation, manifesting as drowsiness or calmness, is a common effect. This can lead to a reduction in alertness and a general slowing of cognitive processes.
Beyond sedation, tranquilizers induce muscle relaxation, alleviating tension and spasms. They also reduce feelings of anxiety and fear, creating a sense of tranquility. Depending on the specific drug and dosage, individuals might also experience impaired coordination, reduced reflexes, and a lessening of pain intensity.
Common Medical Uses
Tranquilizers are prescribed for medical conditions where calming the nervous system is beneficial. They are used for anxiety disorders, including generalized anxiety and panic disorder, to alleviate worry and fear. Their sedative properties also treat insomnia, helping individuals fall asleep and maintain sleep.
Beyond psychological applications, tranquilizers address physical conditions like muscle spasms, providing relief through their muscle-relaxant properties. They control seizures and treat epilepsy. Tranquilizers can also be administered as pre-anesthesia to calm patients before surgery or to manage alcohol withdrawal symptoms.