Notes: N-didesmethyl Loperamide is an active metabolite of the peripheral μ1-opioid receptor agonist loperamide.{67472} It inhibits electricity-induced contractions in isolated guinea pig myenteric plexus (IC50 = 370 nM).{67473} N-didesmethyl Loperamide sensitizes a chloroquine-resistant P. falciparum strain to chloroquine (EC50 = 482 nM) without inducing toxicity in A-10 vascular smooth muscle cells (IC50 = >10,000 nM).{67474}