CHEMISTRY IN EVERY DAY LIFE
LONG ANSWER QUESTIONS
1. Explain the different classifications of drugs. Classifications of drugs: Drugs are classified in different ways. i) On the basis of drug action: Based on the actions of drugs on particular biochemical processes they are classified as i) Antibacterials iv) Sedatives and tranquilizers ii) Antibiotics v) Cardio vascular drugs iii) Hypnotics vi) Antiseptics etc.
ii) On the basis of molecular targets: Biomolecules like Carbohydrates, lipids, proteins, nucleic acids etc. react with dugs. These biomolecules are called drug targets or simply target molecules. iii) On the basis of chemical structure: The drugs with some common structural features generally show similar pharmacological activity. Ex: Sulphonamides have common structural feature. So they have same chemotherapeutic action. 2. Discuss about (i) analgesics and (ii) antipyretics. Ans: Analgesics: Analgesics either reduce or totally abolish pain without causing disturbances of nervous system. These are classified as a) Narcotic analgesics: These are most potent and clinically useful agents causing depression of central nervous system and at the same time act as strong analgesics. Ex: Morphine, Codeine, Heroin etc. The term narcotic drugs now mean addictive drugs. When these are administered in medicinal doses, relieve pain and produce sleep. In high doses they produce coma, convulsions and finally death. Uses: These analgesics are chiefly used for the relief of post operative pain, cardiac pain, cancer pain, cough and induce sleep in the presence of pain.
www.sakshieducation.com b) Non - narcotic analgesics: These drugs are analgesics but they have no addictive properties. Their analgesic use is limited to mild aches and pains like backache and headache. Ex: Aspirin, Ibuprofen etc. Aspirin: Chemically aspirin is ortho acetyl salicylic acid. Preparation: Acetylation of salicylic acid with acetic anhydride gives aspirin. Uses: i) As anti inflammatory, analgesic and antipyretic. ii) It inhibits platelet function and its anti blood clotting action provides to prevent heat attacks. ii) Antipyretics: Antipyretics are defined as those substances which reduce body temperature in fever. Antipyretic drug affects the hypothalamic centre which in turn activates the dilation of the peripheral blood vessels and increases the rate of perspiration which cause the body to loose heat and subsequently lowers the body temperature. Antipyretics have no effect on body temperature when it is in the normal range. Ex: Analgin, Paracetamol. Phenacetin etc. 3. Write a note on i) antimicrobials ii) antiseptics and iii) disinfectants
i) Antimicrobials: Antimicrobials kill or inhibit the growth of organism that cause disease. They increase immunity and resistance to infection of the body. The control of microbial disease is achieved by a) a drug that kills micro organisms in the body. b) a drug which inhibits the growth of organism. Ex: Lysozyme, Lactic acid, Hydrochloric acid in stomach. ii) Antiseptics: The chemical compounds that kill (or) prevent the growth of microorganisms. These are applied to living tissues like wounds, cuts, ulcers and diseased skin surfaces. They are no ingested. Ex: • Mixture of choloroxylenol and terpineol is antiseptic dettol.
www.sakshieducation.com • • • • Bithionol is added to soaps to impart antiseptic. 2 – 3% Iodine in alchoholic aq. Solution known as tincture of iodine is antiseptic. Iodoform is another antiseptic. Boric acid solution is a weak antiseptic for eyes.
iii) Disinfectants: These are chemical compounds used for killing or preventing the growth of microorganisms. These are applied to inanimate objects like floors, drainage systems etc. Ex: • 4% aq solution of formaldehyde called formalin is disinfectant. • 0.3 ppm chlorine aq. Solution is disinfectant. Same chemicals may be used as antiseptic but 1%...