1. Antacids:-

The substances which neutralize the excess of acid produce in the body and raise the PH to an appropriate level in the stomach are called antacids.

Magnesium Hydroxide, Magnesium Carbonate etc.

  • A major breakthrough in treatment of hyperacidity [excess of acid in stomach] is come through the discovery of histamine which stimulates the secretion of pepsin and hydrochloric acid other useful. An acid are Histamine, Cimatedine, and Ranitidine etc.

2. Antihistamines:-

  • Some person suffers hypersensivity to dust, drugs pollen grains, this is due to release of substance histamine in the body. It contracts the smooth muscles in bronchi and gut. Thus it cause allergy, skin rushes
  • Thus the drugs which in terferes with the natural action of histamine by competing with histamine for binding sites of receptor are called Antihistamines. They are used for treatment of Fever, Sneezing, Nasal discharge etc.

3. Neurologically Active Drugs:-
Tranquilizers and analgesics are neurologically active drugs.

a. Tranquilizer:-

  • Drugs which are used for the treatment of stores, fatigue, mild and severe mental diseases are called tranquilizers.
  • Thy relieve anxiety, stress, irritability or excitement by including a sense of well being.

Equanil – it is used for controlling hypertension and depression.
Chlorodiazepoxide, Meprobamate, Serotonin (Iproniazid, Phenelzine):- these are antidepressant drugs.

  • Borbitaric acid and its derivatives:- Veronal, Seconal, Amyful and Nembutal

b. Analgesies:
Neurologically active drugs which reduce or abolish pain without causing impairment of consciousness, mental confusion, in coordination or pyralysis or some other disarder are called Analgesis. They can be categorised into two categories:-

i. Non Narcotic analgesics:-
Aspirin and paracetamol all the good examples of above.

  • Aspirin is used as a pain killer.
  • These drugs are have effects like reducing fever, preventing blood platelet coagulation etc.

ii. Narcotic (addicative) analgesics:-

  • Drugs which when taken in small doses relieve pain and produces sleep are called Narcotics. They are obtained from opium poppy and are called opiates.
  • These are mostly used for relief in post operative pain, cardiac pain, pains of terminal cancer and child birth.

Heroin, Morphine, Codeine, etc.

4. Antimicrobials:-

Drugs which are used to cure diseases caused by microbes or microorganisms.
Such as bacteria, virus and fungi are called.


  • 1st Antimicrobil was arsphenamine called salvarsan for treatment of syphilis
  • In 1932 firt effective antibacterial agent prontosil was discovered.


i. By using a Bacterial drug:-
A drug which kills organism in body.

ii. Using Bacteriostatic drug:-
A drug which inhibits or arrests the growth of organisms.

The chemical substances (Produced wholly or partially by chemical synthesis) which in low concentration, either kill or inhibit the growth of microorganisms by intervening in their metabolic processes.

Types of Antibiotics:-
Bactericidal Bacteriostatic
Penicilin Erythromycin
Aminoglycosides Tetracycline
Ofloxacin Chloromphenicol

  • Penicillin is a very effective drug for pheumonia bronchitis, sore throat etc.
  • The full range of microorganisms attacked by an antibiotic is called spectrum. Broad Spectrum antibiotics are effective against several different types of harmful bacteria.
  • Streptomycin used for curing tuberculosis chloramphenicol for typhoid and pheumonia for cancer cells.


i. Antiseptics:-
Antiseptics are substances which prevents the growth of microorganisms and even kill them. They are safe to apply on living tissues.
Furacin, Safromycin, they are applied to Wounds, Cuts, Ulcers. etc.

ii. Disinfeetants:-
They are chemical substances which kills microorganisms but are not safe to applied on living tissues. They are used to kill germs in drains, toilet, floors etc.

Various disinfectants and antiseptics and their uses in common life:-

1. A low concentration of chlorine 0.2 to 0.4 parts per million (PPm) is used for sterilization of water.

2. Dettol:-
It is a well known antiseptic mixture of chloroxylenol and a – terpinol.

3. Bithional:-
Antiseptic added to good quality soaps to reduce the odors produced by bacterial decomposition of organic matter on skin.

4. Iodine:-

Iodine is a powerful antiseptic. It is used as tincture of iodine (which is 2 – 3% solution of iodine in alcohol and water) applied on wounds.

7. Antifertility Drugs:-

Chemical substances which are used to check pregnancy in women are called antifertility drugs. They are used as birth construal cycle and ovulation.
Nore thindrone, Mifepristone Ethynylestradiol (novestrol).

« Click Here for Previous Topic Click Here for Next Topic »

Class 12 Chemistry Solid States All Topic Notes Class 12 Chemistry All Chapters Notes

Amity University Apply Now!!

Leave a Reply