CLASSIFICATION OF CRUDE DRUGS

CLASSIFICATION OF CRUDE DRUGS

 

There are following methods of classification.

1.      Alphabetic method of classification

2.      Chemical method of classification.

3.      Pharmacological method of classification.

4.      Morphological method of classification.

5.      Taxonomical method of classification.

6.      Chemo- taxonomical method of classification.

1.         Alphabetic Method of Classification

In this method drugs are classified according to first alphabet of their English or Latin name. This method is adopted in many books like I. P. (Indian Pharmacopoeia) N.P. (National formulary) U.S (United states Pharmacopoeia), B.P. In I.P.1955 drugs where given according to Latin name. In I. P. 1966 names changed in to English.

Amylum Changed in to starch

Acacia changed in to Indian gum.

Advantages: -If we know the name of drug, we can study it properly.

2.         Chemical Method of Classification: -

Drugs are classified according to their active chemical constituent. Drugs which

Contain similar chemical are grouped in one place.

Chamical Content	Drugs
1. Volatile oil                        2. Alkaloid                             3. Glycoside                                     4 Fixed oil & fat                               5. Carbohydrates                           6. Vitamins                                       7. Lipid	Fennel oil, coriander. Rauwolfia, Datura Nuxvomica, Cinchona,and Vinca Senna leaf, Digitalis. Arachis oil, sesame oil, castor oil Acacia, Honey, starch, Isapgol Shark liver oil, cod liver oil wheat, Germ oil, Amla. Castor oil, peanut oil, mustard, and wool fat

 

Disadvantages: -

 

1.      This method does not give any idea about source of drug.

2.      Some drugs contain two important chemicals so it is difficult to classify them.

e. g. Nutmeg contains volatile oil as well as fat. Cinchona contains glycoside as well as alkaloid.

3.      No idea whether drug is organized or unorganized.

Advantages: -

If we know chemical constituent. It is easy to study the drug.

Pharmacological Classification: -

The drugs having similar pharmacological effect in body are grouped together.

Pharmacological Action	Drug
1. Carminatives	Fennel, Dill, Coriander, and Clove.
2.  Purgatives	Cascara- sagrada, Aloe, Senna, and Rhubarb.
3.  Cardio tonics	Digitalis, squill, and strophanthus
4.   Anthelmintic	Artemisia, Male- fern, and Quassia
5.  Anti- cancer	Podophyllum, Vinca
6.  CNS Stimulant	Nuxvomica
7.  Expectorant	Vasaka, Liquoric
8.  Bitter tonic	Gentian, Cinchona, and Nux vomica

 

 

Disadvantages: -

1.         Some crude drugs have two different pharmacological actions therefore it is difficult to classify them. E.g. Nux- vomica is CNS stimulant as well as bitter tonic. Cinchona is bitter tonic as well as Antimalarial & Antipyretic.

2.         Drugs that have different mechanism of action have to be grouped together.

e. g. Castor oil is irritant purgative & Isapgol is bulk purgative but they are placed in one       group.

3.         No idea whether drugs are organized or unorganized

4.         This method does not give any idea of source of drugs.

Advantages: -

If we know pharmacological action it is easy to study the drug.

 

Morphological Classification: -

In this method drugs are divided into parts of plants like, Roots, Flowers, Leaves, Wood, Extracts, Gum, Bark.

 

Part of Plant	Drugs
Fruit:	Caraway, Fennel,
Seed:	Nuxvomica, Nutmeg, colchicum
Bark:	Arjuna, Cinchona, cinnamon
Gum:	Acacia, Tragacanth, Streculia, and Guargum
Latex:	Opium, Papaya
Extract:	Catechu, Agar, and gelatin.
Leaf:	Coca, Digitalis, Senna, and Vasaka.

Advantages: -

1.         It is more convenient for practical purpose.

2.         Even if the chemical content or action of drug is not known the drug can be studied properly.

3.         It gives idea about source of drugs

4.         It gives idea whether it is organized / unorganized.

Disadvantages: -

During collection, drying & packing morphology of drug changes. They are difficult to study.

Taxonomical Classification: -

It is purely biological classification. Drugs are given according to position of plant in plant kingdom. It is difficult system.

Disadvantage: -

No idea about organized / unorganized.

Fennel: -

Division                      -           Angiosperm.

Class                          -           Dicotyledonae

Order                          -           Umbelliflorae.

Family                         -           Umbelliferae.

Example                     -           Fennel.

Chemo taxonomical: -

This is recent type of classification in which equal importances have been given to family of plant & it's chemical constituents. It has been found that there is closed relationship between chemical composition of the plant and its position in plant kingdom.

Ex. plants of Umbeliferae contain volatile oil, plants of Solanaceae, Apocyanaceae contain alkaloid.