Loperamide: Death by Lemonade and Conclusions for E-prescribing

Loperamide is a peripherally effective μ-opioid receptor agonist, which is frequently used for the therapy of diarrhea. In normal dose loperamide has no central opioid effects. This is due to the efflux transporter P-gp, which transports any loperamide at the blood-brain barrier back to the peripheral blood system which might have been absorbed before from the blood capillaries into the endothelial cells. If P-gp in these cells is blocked, however, loperamide may penetrate the CNS and develop opioid effects including central and respiratory depression. This is probably the mechanism which was responsible for the fatal outcome of the following case published in the german journal “NeuroTransmitter” under the original title “Tod durch Limonade” (Death by Lemonade)