Medicines or Drugs
Chemicals which may be used for the treatment of diseases and for reducing the suffering from pain are called medicines or drugs .
The branch of science which makes use of chemicals for the treatment of disseases [ therapeutic effect ] is called chemotherapy .
Some important classes of drugs are
Antacid
The chemical substances which neutralize the excess acid in gastric juice and raise the pH to an appropriate level in stomach are raued antacids .
The most commonly used antacids are weak bases such as sodium bicarbonate [ sodium hydrogencarbonate , NaHCO3 ), magnesium hydroxide [ Mg ( OH ) 2 ] and aluminium hydroxide [ Al ( OH ) 3 ].
Generally liquid antacids are more effective than tablets because .. have more surface area available for interaction and neutralisation acid .
Milk is a weak antacid .
Histamine stimulates the secretion of pepsin and hydrochloric acid . The drug cimetidine [ Tegamet ] was designed to prevent the interaction of histamine with the receptors present in the stomach Cimetidine binds to the receptors tbat triggers the release of acid the stomach . This results in release of lesser amount of acid . Now ranitidine ( zantac ), omeprazole and lansoprazole are used hyperacidity .
Tranquilizers ( Psychotherapeutic Drugs )
Chemical substances used for the treatment of stress , anxiety , irritability and mild or even severe mental diseases , are known as tranquilizers . These affect the central nervous system and induce sleep for the patients as well as eliminate the symptoms of emotional distress . They are the common constituents of sleeping pills .
Noradrenaline is one of the neurotransmitter that plays a role in mood change . If the level of noradrenaline is low , the signal sending activity becomes low , and the person suffers from depression . In such situations antidepressant drugs are required . These drugs inhibit the enzymes which catalyse the degradation of noradrenaline . If the enzyme is inhibited , this important neurotransmitter is slowly metabolized and can activate its