Clemastine (HS-592, Meclastine) fumarate (Standard) is the analytical standard of Clemastine fumarate. This product is intended for research and analytical applications. Clemastine fumarate is an orally active, blood-brain barrier-permeable H1 histamine receptor (H1 histamine receptor) antagonist with potent antiallergic effects. Clemastine fumarate also antagonizes muscarinic acetylcholine receptors (mAChR), particularly the M1 and M4 subtypes. In addition to antihistamine effects, Clemastine fumarate exhibits multiple pharmacological activities, especially in promoting central nervous system remyelination, activating autophagy and pyroptosis, exerting anti-apoptotic and neuroprotective effects, and suppressing inflammation [1][2][3][4][5][6].