Central
Nervous System Drugs medical books
Central
nervous system drugs-that is, drugs that affect the
spinal cord and the brain-are used to treat several
neurological (nervous system) and psychiatric problems.
For instance, antiepileptic drugs reduce the activity
of overexcited brain areas and reduce or eliminate seizures.
Antipsychotic drugs are used to regulate certain brain
chemicals called neurotransmitters, which do not function
properly in people with psychoses, major mental disorders
often characterized by extreme behaviors and hallucinations,
such as in schizophrenia. Antipsychotic drugs can often
significantly alleviate hallucinations and other abnormal
behaviors.
Antidepressant drugs reduce mental depression. Antimanic
drugs reduce excessive mood swings in people with manic-depressive
illness, which is characterized by behavioral fluctuations
between highs of extreme excitement and activity and
lows of lethargy and depression. Both types of drugs
act by normalize chemical activity in the emotional
centers of the brain. Antianxiety drugs, also referred
to as tranquilizers, treat anxiety by decreasing the
activity in the anxiety centers of the brain.
Sedative-hypnotic drugs are used both as sedatives to
reduce anxiety and as hypnotics to induce sleep. Sedative-hypnotic
drugs act by reducing brain-cell activity. Stimulatory
drugs, on the other hand, increase neuronal (nerve cell)
activity and reduce fatigue and appetite.
Analgesic drugs reduce pain and are generally categorized
as narcotics and non-narcotics. Narcotic analgesics,
also known as opioids, include opium and the natural
opium derivatives codeine and morphine; synthetic derivatives
of morphine such as heroin; and synthetic drugs such
as meperidine and propoxyphene hydrochloride. Narcotics
relieve pain by acting on specific structures, called
receptors, located on the nerve cells of the spinal
cord or brain. Non-narcotic analgesics such as aspirin,
acetaminophen, and ibuprofen reduce pain by inhibiting
the formation of nerve impulses at the site of pain.
Some of these drugs can also reduce fever and inflammation.
General anesthetics, used for surgery or painful procedures,
depress brain activity, causing a loss of sensation
throughout the body and unconsciousness. Local anesthetics
are directly applied to or injected in a specific area
of the body, causing a loss of sensation without unconsciousness;
they prevent nerves from transmitting impulses signaling
pain.
|