Astemizole is a second-generation H1 antihistamine once widely used for allergic rhinitis, later withdrawn in most markets after its CYP3A4-dependent QT-prolongation risk was identified. Simson Pharma's Astemizole reference standard supports legacy formulation QC and comparative antihistamine research.

Simson Pharma Global Ltd. (UK) and Simson Pharma Global LLC (USA) supply high-quality Astemizole Reference Standards, pharmacopoeial reference materials, and its related impurities to pharmaceutical manufacturers, CROs, analytical laboratories, universities, and regulatory organizations worldwide. To service the Europe and America market efficiently, Simson Pharma Limited has set up Simson Pharma Global Ltd. in United Kingdom and Simson Pharma Global LLC in USA respectively.