The mechanism of action of "Terfenadine" $(Seldane)$ is :-

Which of the following is not an antibiotic?

Which of the following substances used as an analgesic is non-narcotic?

In the given reaction scheme,$P$ is a phenyl alkyl ether,$Q$ is an aromatic compound; $R$ and $S$ are the major products.
$P$ $\xrightarrow{HI} Q$ $\xrightarrow[\text{(iii) } H_3O^{+}]{\text{(i) } CO_2, \text{(ii) } NaOH} R$ $\xrightarrow[\text{(ii) } H_3O^{+}]{\text{(i) } (CH_3CO)_2O} S$
The correct statement about $S$ is:

Chloroxylenol is an example of

Define drugs and explain their classification.