The central nervous system refers to the brain and spinal cord. They are (brain & spinal cord) are the main "processing center" for the entire nervous system, and control all the functions of the body. The central nervous system does not include the peripheral nerves in the arms, legs, muscles, and organs.
Central nervous system drugs are used to treat the effects of a wide variety of medical conditions, including Alzheimer's disease, depression, and Parkinson's disease. This category of medication also includes analgesics (drugs for pain relief), sedatives, and anticonvulsants. Central nervous system or CNS drugs affect the brain and spinal chord. They are also used for sedation and in surgery as general anesthetics. Anticonvalsants are used for the treatment of seizure disorders. Antidepressants are psychotropic agents used for some aggression and behavioral disorders.
Central Nervous System depressants slow normal brain function. In higher doses, some drugs can become general anesthetics. Tranquilizers and sedatives are examples of central nervous system depressants. central nervous system depressants can be divided into two groups, based on their chemistry and pharmacology - Barbiturates & Benzodiazepines.
Central nervous system stimulants increase alertness, attention, and energy, which are also accompanied by increases in blood pressure, heart rate, and respiration. Earlier, stimulants were used to treat asthma and other respiratory problems, obesity, neurological disorders, and many other ailments. However, as their potential for abuse and addiction became apparent, their use began to wane. Nowadays, stimulants are prescribed for treating only a few health conditions, like narcolepsy, attention-deficit hyperactivity disorder (ADHD), and depression that has not responded to other treatments. Central nervous system stimulants may also be used for short-term treatment of obesity and for patients with asthma.
Anticonvulsant drugs such as carbamazepine, phenytoin, and gabapentin are used to control seizures and other symptoms of epilepsy. They work by selectively reducing excessive stimulation in the brain. Also, these drugs may be used to prevent and treat certain types of pain. The manner in which anticonvulsant drugs work is not clearly understood.
Alzheimer's Disease is considered a disease of central nervous system. There are several drugs available to help slow the decline in mental abilities in people who suffer from Alzheimer's disease. Alzheimer's disease is an incurable disease that causes gradual deterioration in brain function. These drugs work by enhancing the amount of a substance called acetylcholine in the brain. Commonly used drugs are donepezil, rivastigmine, and galantamine.
Antipsychotic drugs or tranquilizers are usually prescribed for patients who are suffering from psychoses (certain types of mental disorders). These drugs calm certain areas of the brain but permit the rest of the brain to function normally. They act as a screen that allows the transmission of some nerve impulses but restricts the passage of others. The antipsychotic drugs frequently used are haloperidol, lithium, chlorpromazine, and thioridazine. Clozapine, olanzapine, and quetiapine are newer agents.
A progressive neurological disorder, Parkinson's disease is caused by a chemical imbalance in the brain. People who have Parkinson's disease experience uncontrollable tremors, develop a characteristic stoop, and eventually become unable to walk. Drugs such as benztropine, bromocriptine, levodopa, selegiline, and trihexyphenidyl are used to correct the chemical imbalance in the brain, thus helping to relieve the symptoms of the disease.
The key central nervous system drugs available are antidepressant, ergot derivative, sedative, antipsychotic, benzodiazepine and antiemtic.