Anaesthetics

The drugs which produce loss of sensation are called anaesthetics. They

are classified into two types. (i) General anaesthetics are the agent, which

bring about loss of all modalities of sensation, particularly pain along with

‘reversible’ loss of conciousness. (ii) Local anaesthetics prevent the pain

sensation in localised areas without affecting the degree of conciousness.

(i) Nitrous oxide N2O : It is a colourless, inoragnic non-irritating gas.

It is the safest of the anaesthetic agents. This is used after mixing general

anaesthetics like ether.

(ii) Chloroform CHCl3 : Volatile liquid. It has pleasent smell and sweet

taste. With oxygen it forms a toxic carbonyl chloride. Hence it is not used

now.

(iii) Ether : The present form of C2H5–O–C2H5 is a volatile liquid. This

is mixed with stabilizer 0.002% propyl halide. After absorption by tissues it

attacks the central nervous system and makes unconcious