astemizole

Astemizole (Laridal) is a synthetic piperidinyl-benzimidazol derivative with antiallergic properties, acts as a reversible competitive inhibitor of histamine H1 receptors, with less anticholinergic effects compared to related agents. It is a long-acting, non-sedative antihistaminic used in the treatment of seasonal allergic rhinitis, asthma, allergic conjunctivitis, and chronic idiopathic urticaria.

Astemizole (Standard) is a reference standard for quantitative analysis, quality control, and biochemical experiments. Astemizole (Laridal) is a long-acting, non-sedating antihistamine. It acts as a histamine H1 receptor antagonist (IC50 = 4 nM) and an hERG K+ channel blocker (IC50 = 0.9 nM), exhibiting anticholinergic and antipruritic effects. It is indicated for inflammatory conditions such as rhinitis and asthma.

Tecastemizole (R 43512) is a selective antagonist of H1 receptor and a major metabolite of astemizole with anti-inflammatory effects.

Desmethylastemizole (O-Demethylastemizole) is a metabolite of Astemizole and acts as a β-hematin (βH) inhibitor. It exhibits antimalarial activity against Plasmodium falciparum strains Pf3D7, PfDd2, and PfItG with IC50 values of 0.12 μM, 0.11 μM, and 0.06 μM, respectively. Additionally, Desmethylastemizole functions as a histamine H1 receptor antagonist and significantly blocks the hERG K+ channel while inhibiting the activity of the histone-lysine N-methyltransferase EZH2. It is utilized in studies of long QT syndrome and malaria.

Noberastine citrate, a histamine H1 antagonist, has potent and specific peripheral antihistaminic activity. Noberastine, a furan derivative of nor-astemizole (an astemizole metabolite), has been shown to have a more rapid onset, and shorter duration of action than astemizole with peak antihistaminic activity at 4h following ingestion. Noberastine is rapidly absorbed and the peak plasma levels are obtained within 2 h of oral dosing. In preclinical studies Noberastine has been shown to lack central nervous system effects. After subacute (steady-state) administration of noberastine, there was increasing inhibition of weal and flare formation with higher doses of the drug. The 30 mg daily dose showed maximum antihistaminic effects.

Noberastine maleate, a histamine H1 antagonist, has potent and specific peripheral antihistaminic activity. Noberastine, a furan derivative of nor-astemizole (an astemizole metabolite), has been shown to have a more rapid onset, and shorter duration of action than astemizole with peak antihistaminic activity at 4h following ingestion. Noberastine is rapidly absorbed and the peak plasma levels are obtained within 2 h of oral dosing. In preclinical studies Noberastine has been shown to lack central nervous system effects. After subacute (steady-state) administration of noberastine, there was increasing inhibition of weal and flare formation with higher doses of the drug. The 30 mg daily dose showed maximum antihistaminic effects.