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.
Analgesic drugs reduce pain and are generally categorized as narcotics and non-narcotics.
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. F. Anticancer Drugs Print section Anticancer drugs eliminate some cancers or reduce rapid growth and spread.