1. Introduction to Pharmacognosy
B. Pharm. IV Sem
By- P. S. Agrawal
(M. Pharm.)

2. OBJECTIVES-
• Introduction
• History of Pharmacognosy
• Scope
• Classification of drugs

3. Introduction
• Pharmacognosy is the study of medicinal uses of crude drugs obtained
from plants and natural resources.
• Crude drugs are dried, raw materials of plant, animal or mineral origin,
used for the medicinal purpose.
• Pharmacognosy- Greek words: “pharmakon” meaning drug, and
“gnosis” meaning to acquire knowledge of.

4. History of Pharmacognosy
• Hippocrates (460 – 370 B.C.) deals with anatomy and physiology ”Father
of Medicine”
• Aristotle (384-322 B.C.) wrote about the animal kingdom.
• Theophrastus(370-287 B.C.) wrote about plant kingdom and described
medicinal uses of plants
• Charak (3000 B.C.) in Charak Samhita made fifty groups of ten herb each
to suffice physician’s need
• Sushrutha- arranged 760 herbs in 7 sets based on common properties in
Sushrutha Samhita

5. Continued..
• Dioscordies (40 – 80 B.C.) in De Materia Medica described 600
medicinal plants.
• Galen (131 – 200 A.D.), the first pharmacist, described methods of
preparing drugs of vegetable and animal origin and laid down many
formulas contained in a thesis of 20 volumes.

6. Scope of Pharmacognosy
ISOLATION OF PHYTOCHEMICALS
▪ Glycosides from digitalis leaves
▪ Alkaloids from the plants of Rauwolfia, Belladonna
▪ Morphine and other alkaloids from the opium
NATURAL PRODUCTS AS MODELS FOR SYNTHESIS OF NEW DRUGS
▪ Morphine is the model of a large group of potent drugs
▪ Atropine for certain spasmolytics
▪ Codeine for local anaesthetics
DRUGS OF DIRECT THERAPEUTIC USE
▪ Steroids, Vincristine, Antibiotics

7. Continued..
CULTIVATION AND COLLECTION OF MEDICINAL PLANTS
▪ Clove, Senna, Cinchona, Opium
PREPARATION OF HERBAL FORMULATIONS
▪ Churnas, Asvas, Lehas

8. Organized crude drugs Unorganized crude drugs
1. As the term indicates these are organs of plants or
animals and are made up of cells or definite structure.
These drugs are named as flowers, seeds, fruits.
insects, etc.
1. These are derived from parts of plant or animal by
some process of extraction and followed by
purification, if necessary ex. juices, extracts, resins
etc.
2. These are solid in nature. 2. These are solid, semisolid or liquids in nature e.g.
oils, gums and balsams.
3. Botanical or zoological terminology can be used to
describe these drugs.
3.Such terminology is inadequate to describe them,
but one has to look for their physical characters, such
as the solubility in various solvents, density, optical
rotation, refractive index, etc. whichever is
applicable.
4. Microscopic characters are one of the important
criteria for the identification of organized drugs.
4. Chemical tests and physical standards are
confirmatory tests Examples: Aloe, agar, colophony,
opium, castor oil, bees-wax, pepsin, etc.
Difference between Organized and Unorganized drugs

9. Classification of crude drugs
Alphabetical classification
Crude drugs are arranged according to alphabetical order of their name.
➢British Pharmacopoeia (BP)
➢ Indian Pharmacopoeia (IP)
➢European Pharmacopoeia (EP)
➢British Herbal Pharmacopoeia (BHP)
➢British Pharmaceutical Codex (BPC)
➢United States Pharmacopoeia (USP)

10. Morphological classification
• The drugs are arranged according to the parts of the plants used such
as leaves, stems, roots, barks, etc.
• The drugs that represent cellular portion of plant are organized drugs
and the drug that represent no cellular structure are unorganized drugs
Organized drugs
Parts of plant
roots and rhizomes - rhubarb
Barks – Cinnamon, cinchona
Leaves – Adhatoda, eucalyplus
Flowers – Rose, saffron

11. Unorganized drugs
▪ Fixed oil - Castor oil
▪ Volatile oil – Turpentine oil
▪ Dried latex - Opium
▪ Dried juice –Aloe
▪ Dried extracts - gelatin
▪ Resin –Benzoin

12. Pharmacological classification
Drugs are classified according to the pharmacological action of the drugs
• Pharmacological action
Cardiotonic – Digitalis, Squill
Carminative - Coriander, clove
Anticancer - Vinca, Taxus
Expectorant - Vasaka
Tranquilizer - Rauwoifia
Analgesic –Opium, Cannabis
Antiinflammatory - turmeric

13. Taxonomical classification
The crude drugs are classified according to the botanical classification.
Drug - Fennel
Division - Angiosperm
Class - Dicotyledons
Family – Umbeliferae
Species – vulgare
Drug - Nuxvomica
Division - Angiosperm
Class - Dicotyledons
Family – Loganiaceae
Species – nuxvomica

14. Classification according to Chemical constituent
The drugs are classified on the basis of chemical constituent present.
1. Glycosides - Digitalis, senna, liqourice
2. Alkaloids - Nuxvomica, cinchona, datura
3. Tannins - Myrobalan, pale catechu, ashoka
4. Volatile oils - Peppermint, clove, eucalyptus
5. Lipids - Castor oil, cod liver oil
6. Carbohydrates -agar, guar gum, pectin
7. Resins & resin derivatives - Colophony, jalap. Balsam of Tolu
8. Vitamins & Hormones - Oxytocin, Insulin
9. Proteins & Enzymes - casein, gelatin, papain

15. References-
• Pharmacognosy by CK Kokate, AP Purohit, SB Gokhale, Nirali
Publication, Pg. 1.1 – 1.13