Classification of Local Anaesthetics

CLASSIFICATION

Local anaesthetics are generally classified into the following groups :

1. Natural agents

1. Cocaine

2. Synthetic nitrogenous compounds

1. Derivatives of benzoic acid

2. Derivatives of para-amino benzoic acid

1. Freely soluble: Procaine, Amethocaine.

2. Poorly soluble: Benzocaine, Orthocaine

3. Derivatives of acetanilide: Lignocaine, Mepivacaine, Bupivacaine, Prilocaine, Etidocaine.

4. Derivatives of quinoline: Cinchocaine, dimethisoquin

3. Synthetic non-nitrogenous agents: Benzyl alcohol, propanediol

4. Miscellaneous drugs with local action: Clove oil, phenol, chlorpromazine and certain antihistamines, for example, diphenhydramine

On the basis of chemical structure, local anaesthetics are classified as follows:

I. Benzoic acid derivatives

II. p-Amino benzoic acid derivatives

III. Anilide derivatives (2,6 Xylidines)

IV. Miscellaneous