These are the chemical substances which are used to cure the disease or reducing the pain are called Drugs.
The use of chemicals which are drugs to destroy microorganisms that cause disease without causing any harm to the host is called Chemotherapy.
The medicines which are used to bring down the body temperature in case of fever.
For Example- Paracetamol, Aspirin, Analgin, Phenacetin, etc.
These are the medicines which are used for relieving the pain. They are Classified into two Categories:-
(a) Narcotic Drugs
(b) Non-Narcotic Drugs
They are mainly opium, alkaloids, and products like codeine, marijuana, heroin, morphine. They are obtained from the opium plant OP. They are highly potent drugs and their chronic use leads to addiction. They are mainly used for relief of pain like pain after surgery, cardiac pain, pain related to cancer.
They are not very potent analgesics, but they do not cause addiction also, they have anti-pyratic properties.
For Example- Aspirin, Analgin, Naproxan, etc.
Malaria is caused by Plasmodium. These are the medicines that are used to bring down body temperature during malaria fever.
Originally, Quinine was the main alkaloid that was effective against malaria which is obtained from the bark of the cinchona tree. Nowadays, medicines that are used are chloroquine, primaquine, pyrimethamine, etc.
ANTISEPTICS AND DISINFECTANTS
Chemical substances which prevent the growth of microorganisms but they are not harmful to human tissues are called antiseptics, they can be applied directly to the body without any harm. They may also be used to reduce the odor composed by bacterial decomposition on the body.
For Example]- Dettol, Savlon, Boric acid, Hydrogen Peroxide, etc.
Chemical substances which kill microorganisms but stop their growth and are harmful to human tissues are called Disinfectants. They kill the bacteria immediately. They are used for the sterilization of non-living substances like vessels, clothes, floors, etc. They cannot be used on the skin.
For Example- phenol, methyl phenols, Chlorine, Bleaching powder, etc
The same substance can act as both depending upon the concentration. In smaller concentrations, it is antiseptic but in higher concentrations, it is disinfectant.
For Example- 0.2% of phenol is antiseptic whereas 1% solution is disinfectant.
These are the chemical substances which are used to cure diseases caused by Bacteria, Fungi, Viruses, etc.
They are further classified as:-
These are a group of drugs which are derivatives of para-amino benezene sulphonamide and they have anti-bacrterial activity.
For Example- Sulphapyridine, Sulphadiazine, Sulphathiazole, Sulphaacetamide, etc.
They are active against a number of gram positive and gram negative negative bacteria.
These are the substances which are produced by certain microorganisms and can be used to kill other microorganisms.
The first antibiotic penicillin was discovered by Sir Alexandra Flemming. It was obtained from penicillium notation which is a fungus.
Penicillins are sparingly soluble in water but their sodium and potassium salts are solube in water. They are active against gram positive bacteria but not active against gram negative bacteria.
The antibiotics can also be classified as Bactericidal or Bacteriostatic.
Bactericidal means which kill the bacteria whereas bacteriostatic means which inhibit the growth of bacteria.
They are a different class of antibacterial drugs which are neither sulphadrugs nor antibiotics, but they are deratives of quinolone.
For Example- Ciprofloxacin, Norfloxacin, etc.
Histamine is a chemical which is released in the body at the time of allergic reaction. Therefore, Antihistamines are the drugs which are able to diminish/ abolish the effect of histamines.
They are also called anti-allergy drugs.
For Example- Brompheniramine, Terfenadine, Cetrizine, etc
The substances which are used to reduce or neutralize Gastric acidity and raise the pH to appropriate level in the stomach are called Antacids.
For Example- Baking Soda, Magnesium oxide, Magnesium trisilicate, Calcium Carbonate, etc.
The drugs which produce insensibility to vital functions of all types of cells especially of the nervous system are called Anaesthetics. The effect produced by them is reversible, therefore, they produce a temporary insensibility to pain or a feeling in the whole of the body or a particular organ.
They are of two types:-
They depress the central nervous system to such an extent that all sensibility to pain or feeling is lost, that is why they produce conscienceless over the body, so they are used for major surgical operations.
For Example- Chloroform, Diethylether, vinylethers, etc.
They affect only a part of the body to make it insensitive to pain or feeling. They are used for small surgical operations like tooth extraction, stitching of wounds, etc.
For Example- Navocaine, Procaine, Xylocaine, etc.