Chemistry in Everyday Life Flashcards
(39 cards)
Drugs
Drugs are chemicals of low molecular masses. When the biological response is therapeutic and useful, these chemicals are called medicines. Use of chemicals for therapeutic effect is called chemotherapy.
Classification on pharmacological effect
-analgesics: have pain killing effect
-antiseptics: kill or arrest the growth of microorganisms.
Classification on drug effect
antihistamines inhibit the action of the compound, histamine which causes inflammation in the body
Macromolecules in body
proteins which perform the role of biological catalysts in the body are called enzymes, those which are crucial to communication system in the body are called receptors. Lipids and carbohydrates are structural parts of the cell membrane
Enzyme action
Substrates bind to the active site of the enzyme through a variety of interactions such as ionic bonding, hydrogen bonding, van der Waals interaction or dipole-dipole interaction. The second function of an enzyme is to provide functional groups that will attack the substrate
Competitive inhibitor
Drugs compete with the natural substrate for their attachment on the active sites of enzymes. Such drugs are called competitive
inhibitors
Allosteric site
Some drugs do not bind to the
enzyme’s active site. These bind to a different site of enzyme which is called allosteric site. It changes the shape of the active site in such a way that substrate cannot recognise it.
Antagonists
Drugs that bind to the receptor site and inhibit its natural function are called antagonists. These are useful when blocking of message is required.
Agonists
Types of drugs that mimic the natural
messenger by switching on the receptor, these are called agonists. These are useful when there is lack of natural chemical messenger.
Why are metal hydroxides better antacids?
Metal hydroxides are better alternatives because of being insoluble, these do not increase the pH above neutrality.
Antacids
The drug cimetidine (Tegamet), was designed to prevent the interaction of histamine with the receptors present in the stomach wall. It was the largest selling drug till ranitidine (Zantac).
Antacids examples
Cimetidine (Tegamet)
Ranitidine (Zantac)
Histamine functions
-a potent vasodilator
-contracts the smooth muscles in the bronchi and gut and relaxes other muscles in the walls of fine blood vessels.
-responsible for the nasal congestion
-stimulates the secretion of pepsin and hydrochloric acid in the stomach
-causes inflammation in the body
Antihistamine
-brompheniramine (Dimetapp)
-terfenadine (Seldane)
Neurologically Active Drugs
Tranquilizers and analgesics are neurologically active drugs. These affect the message transfer mechanism from nerve to receptor
Noradreline
noradrenaline is one of the neurotransmitters that plays a role in mood changes
Anti-depressants
-Iproniazid
-phenelzine (Nardil)
Tranquilizers
-chlordiazepoxide
-meprobamate
-Equanil (Controls depression and hypertension)
-valium
-serotonin
Barbiturates
Derivatives of barbituric acid viz., veronal, amytal, nembutal, luminal. Barbiturates are hypnotic, i.e., sleep producing agents.
Analgesics
Analgesics reduce or abolish pain without causing impairment of consciousness
Non-Narcotic drugs
-Asprin (inhibits prostaglandins; reducing fever (antipyretic) ;preventing platelet coagulation; use in prevention of heart attacks.)
-Paracetamol
Narcotic analgesics
-Morphine
-Heroin
-Codeine
Antibiotics
An antibiotic refers to a substance produced wholly or partly by chemical synthesis, which in low concentrations inhibits the growth or destroys microorganisms by intervening in their metabolic processes.
Syphillis
-arsphenamine, known as salvarsan
-salvarsan had -As=As- linkage
-the first effective antibacterial agent, prontosil, which resembles salvarsan. In the body prontosil is converted to a compound called sulphanilamide, which is the real active compound
