Medicines and Drugs

General Science (Easy) Chemistry

Medicines and Drugs

The living body is made of chemical substances. Any foreign chemical substance that enters a living body can hence react with body tissues and fluids. By inducing suitable chemical reactions in the body through chemicals, diseases can also be controlled. Chemicals used in this way are known as medicines. Chemistry helps in identifying chemical substances that can control disease. Chemicals that can react with protein molecules are usually used as medicines. All the processes in the living body are controlled through enzymes which are proteins. This is why chemicals that react with proteins are used as medicines. For example, when antibiotics react with enzymes in the bacterial cell they are destroyed or their growth stopped.
Chemical used to frequently classified according to their action.
Analgesics- relieve pain
Antipyretics- reduce temperature
Anti-inflammatory- control inflammation
Antibiotics- kill bacteria and other microorganisms.

These chemicals bring down body temperature during high fever and the patient. Commonly used chemicals are aspirin, phenactin and paracetamol.

These drugs relieve pain. Aspirin and some other antipyretics act as analgesics certain narcotics, i.e. morphime, marijuana, codeine and heroin are also used as analgesics.

These chemicals kill or prevent the growth of microorganisms.
Antiseptics are applied to the living tissues, and this applicable to wounds, cuts, ulcers and diseased skin surfaces, and also used as deodorants & breath purifiers.
Disinfectants kill microorganisms that live in inanimate items like floor, instruments etc.
Phenol is used as both, 0.2% solutions of phenol as antiseptic and 1% solution of phenols as disinfectants.
Chlorine is used for making drinkable water by adding a concentration of 0.2 to 0.4 ppm.
Low concentration of sulphur dioxide is used as preservatives in squashes.
Bithional imparts antiseptic properties to the soap, and reduces undesirable odours from skin.
Tincture of iodine, is a powerful antiseptic.
Iodoform was widely used as an antiseptic powder.
Organic dyes such as gentian violet and methylene blue are used as antiseptic dyes.

Tranquilizers are substances that are used for the treatment of mental diseases, and act on central nervous system. They are constituents of the sleeping pills, and helping the patient by alleviating symptoms, which interferes with sleeping function of the brains.
Derivatives of the barbituric acid are known as tranquilizers since long times.
Equanil is too used in depression and hypertension.

Antibiotics are chemicals produced by microorganisms (bacteria, fungi and molds) that stops or destroys the growth of other microorganisms.
Penicillin was the first antibiotic, obtained from the mold Penicillin notatum. It is used against large number of infections like pneumonia, bronchitis, sore throat and abcesses, caused by cocci, gram positive bacteria.
Streptomycin (produced from Straptomycetes) and tetracycline are used against diseases caused by gram-negative bacteria, which have penicillin resistant capability.
Streptomycin is effective against TB and while chloramphenicol for typhoid.
Chloramphenicol is an antibiotic that is effective against many disease-causing germs. Since this substance is easily absorbed in the alimentary tract, this is applied as oral medicine in diseases like typhoid, cholera, meningitis, pneumonia etc.

A narrow spectrum antibiotic is Penicillin. Penicillin is produced in commercial production by using the Penicillium chrysogenum and its various mutants. Its production involves and large-scale fermentation. The patient’s sensibility (allergy) is required before it is administered.
Ampicillin and amoxicillin are semi synthetic modifications of Penicillin.

Chloramphenicol

It is a broad spectrum antibiotic.
It is give orally and it is rapidly absorbed from the gastro-intestinal tract.
It is effective against typhoid, dysenetery, acute fever, certain urinary infections, meningitis and pneumonia.

Sulpha drugs like sulphanilamide, sulphadiazine and sulpha guananidine act against micro organisms like anti-biotics

Drug	Sport in which used	Performance enhancing effect	Negative effect
Steroids	Football, track, body building, field events, weightlifting	Increases muscle mass and strength. Helps muscles recover quickly from fatigue	Men: hair loss, testicular atrophy Women: Irregular menstruation Disease : sterility
Amphetamines	All sports except those in which steady nerves and concentration are required	Heightens alertness; postpones onset of fatigue	Feelings of anxiety and restlessness
Betablockers	Archery, shooting, jumping, figure skating	Slows the heart beat and steadies body movements	Can cause asthma, impair mental alertness, lead to impotence
Human Growth Steroid substitute		Promotes muscle growth and strength not detectable by common testing methods	Brain damage, can result in hormones, dehydration
Diecuretics	Body building boxing, weightlifting and wrestling. All sports in which competitors are grouped in weight classes	Reduces weight quickly by hastening excretion of urine	Cramps: loss of sodium and potassium: kidney damage
Erythopoietin	Long distance running, cycling and cross country skiing	Bolsters endurance by increasing the blood’s supply of oxygen- carrying red cells. Not detectable by current testing methods	Thickening of the blood to a point where clots may from triggering a stroke or a heart attack