Antihistaminic;H1 antogonist
H1 receptor antagonist. Anxiolytic. Antihistaminic.
Hydroxyzine dihydrochloride has been used in the study of comparative anxiolytic activity of various drugs in experimental models of rats.
A mixture of 0.1 mol of N-mono-1-p-chlorobenzohydrylpiperazine and 0.1 mol
of 1-chloro-2-(2-hydroxy-ethoxy)-ethane is heated for 3 hours to 150°C. The
mass is then taken up in 100 ml of benzene and 100 ml of a 10% aqueous
solution of NaOH; decanting takes place, and the benzene solution is washed
with water and the solvent is evaporated. Vacuum distilling of the residue
yields 1-p-chlorobenzohydryl-4-[2-(2-hydroxy-ethoxy)-ethyl]-piperazine, BP
220°C/0.5 mm Hg.
The corresponding dihydrochloride is prepared by dissolving this base in about
twice its weight of alcohol, by treating it with excess of gaseous HCl and by
precipitating it with ether. The solvent is decanted and the residue, dissolved
in a minimum of alcohol, crystallizes on the addition of ether, MP 193°C.
Hydroxyzine dihydrochloride is an antihistaminic drug and a member of the diphenylmethanes family. It exerts its action by blocking the action of histamine, a substance in the body that causes allergic symptoms.
Pharmaceutical secondary standards for application in quality control, provide pharma laboratories and manufacturers with a convenient and cost-effective alternative to the preparation of in-house working standards.
Hydroxyzine dihydrochloride (HDH) is used to regulate anxiety. It is also used to treat bronchial asthma and to relax patients before surgery.
