Loperamide hydrochloride

Loperamide hydrochloride is an opioid-receptor agonist and acts on the μ-opioid receptors. Loperamide exhibited potent affinity and selectivity for the cloned micro (Ki = 3 nM) compared with the delta (Ki = 48 nM) and kappa (Ki = 1156 nM) human opioid receptors. Loperamide potently inhibited forskolin-stimulated cAMP accumulation (IC50 = 25 nM) in Chinese hamster ovary cells transfected with the human mu opioid receptor. Loperamide hydrochloride is also a Ca2+ channel blocker. Loperamide hydrochloride blocks broad spectrum neuronal HVA Ca2+ channels at low micromolar concentrations and at higher concentrations it reduces Ca2+ flux through NMDA receptor operated channels. Loperamide is effective for the treatment of a number of types of diarrhea.