<unk>  is a H1 antihistamine with low potential for causing drowsiness. It does not penetrate the blood–brain barrier to a significant amount and thus combines an effective block of the H1 receptor in peripheral tissue with a low incidence of central side effects, i.e. seldom causing sedation or drowsiness. It was patented in 1983 by Almirall S.A and came into medical use in 1990. The substance is often provided in micronised form due to poor water solubility.
Ebastine
Clemastine
Azelastine
Pemirolast
Pentagastrin
Altretamine
Hydrastine
Seratrodast