The active drugs on the central nervous system affect the functioning of the brain and spinal cord, exerting an action that can help cure or alleviate certain medical conditions, such as disease Alzheimer's disease, Parkinson's disease and depression as well as other conditions. In this family of drugs, also belong the active ingredients that help fight pain, as well as sedatives and muscle relaxants.


Among the main categories of these drugs are included:


  • The colinergic agonists: they are used to increase salivation in case of dry mouth. They act by stimulating the parasympathetic nervous system.


  • The analgesics: these are drugs used to relieve pain. The so-called narcotics, opium derivatives, act directly on the brain by binding to receptors involved in the perception of pain sensation and they can also be used as a sedative for coughs. The most popular among non-narcotic analgesics, NSAIDs, act instead on the synthesis of prostaglandins, which are important mediators of inflammation.


  • The general anesthetics: they are used to prevent pain during surgery and act by inducing a state of unconsciousness.


  • The anorectic: they are used to reduce appetite because they act on an area of the brain that inhibits hunger, but they also apply in the case of keeping a person awake, accelerate the heart rate or increase the blood pressure.


  • The anticonvulsants: they are used to control seizures typical of epilepsy and work by reducing the excessive stimulation of the nervous system typically associated with this disorder. Their possible mechanisms of action include the increased activity of the neurotransmitter GABA and the inhibition of calcium channels or of glutamate receptors. Sometimes they are also used to prevent and treat certain types of pain.


  • The antidepressants: they are used to treat depression, episodes of panic attacks, to combat obsessive-compulsive disorder as well as to prevent certain types of migraine and other forms of pain. The mechanism at the basis of their pain-killing effect has not yet been fully clarified, while the antidepressant action follows different paths depending on the molecule considered. Some, for example, maintain high levels of serotonin, the so-called "hormone of humor."


  • The antiemetics: they are used to control vomiting and dizziness and act on brain receptors that trigger the urge to empty the stomach.


  • The antipsychotics and tranquilizers: they act by inhibiting the activity of specific nerve impulses and are used to treat psychosis.


  • Drugs against Parkinson’s disease: they correct the alteration of chemical equilibrium of the brain that is typical of this disease, thus helping to alleviate the symptoms. In particular, anticholinergic agents (or acetylcholine antagonists) block the muscarinic receptors of the neurotransmitter acetylcholine, while dopaminergic agents replace the neurotransmitter dopamine or prevent their degradation.


  • Medications against alcohol addiction: these may act differently between them. Some, for example, reduce the desire to drink that leads to withdrawal symptoms, while others cause nausea and vomiting if taken with alcohol, and thus discourage its consumption.


  • The stimulants of the central nervous system: they are used in case of attention deficit disorder/hyperactivity disorder and narcolepsy. Their exact mechanism of action is not known.


  • The hypnotic drugs: they are used in case of insomnia. The two main classes are barbiturates and benzodiazepines. Both act by increasing the effect of the neurotransmitter GABA.


  • The inhibitors of cholinesterase: they are used to treat dementia in people with Alzheimer’s disease. They act by increasing the activity of the nerves stimulated by the neurotransmitter acetylcholine.


  • The muscle relaxants: they are used to relieve muscle spasms and sometimes, musculoskeletal pain or to relax the voluntary muscles during surgery. In the first case, their mechanism of action is based on the reduction of muscle tone; while in the second case, they act on the transmission of nerve impulses to the muscle.


  • The sedatives and Anxiolytics: they are used for the treatment of anxiety, panic attacks and insomnia and work by reducing the levels of several specific molecules in the brain.


How should central nervous system drugs be taken?


The drugs that act on the central nervous system can be taken in various forms and in very different ways to each other. Some are available in the form of pills or drops, for example antidepressants and sedatives. Others such as muscle relaxants may be taken by intramuscular injections. Anesthetics, however, can be injected into a vein or administered in gaseous form.

In any case it is essential to follow the doctor's instructions in terms of dosage and mode of application.


Contraindications and warnings associated with the use of central nervous system drugs


The drugs active on the central nervous system should be taken under medical supervision. The main adverse effects can vary according to the type of drug and may include dependence, as in the case of narcotics, and loss of effectiveness associated with prolonged use, as in the case of amphetamines taken as anorectics. Other possible side effects include headaches, nausea, restlessness, insomnia, nervousness, drowsiness, visual disturbances, sexual problems, dry mouth, constipation and bladder problems. Moreover, these drugs often affect the ability to drive or operate hazardous machinery.