Disclosed herein is one pot synthesis for preparation of meclizine hydrochloride which comprises sequential bromination of m-xylene to obtain 3-methyl benzyl bromide followed by in situ condensation of bromocompound with 4-chloro benzhydryl piperazine in the presence of acid acceptor to give meclizine base of formula I, which on treatment with hydrochloric acid to obtain meclizine hydrochloride salt. The invention further discloses the effective purification of meclizine base with citric acid to obtain meclizine hydrochloride substantially free from dimeric impurity in the next step.
