Case Report: Opioid Use Disorder Associated With Low/Moderate Dose of Loperamide in an Intellectual Disability Patient With CYP3A and P-Glycoprotein Reduced Activity

Vincent Guinchat; Nicolas Ansermot; Kuntheavy Ing Lorenzini; Dimitri Politis; Youssef Daali; Chin B Eap; Séverine Crettol

doi:10.3389/fpsyt.2022.910684

Case Report: Opioid Use Disorder Associated With Low/Moderate Dose of Loperamide in an Intellectual Disability Patient With CYP3A and P-Glycoprotein Reduced Activity

Front Psychiatry. 2022 Jun 23:13:910684. doi: 10.3389/fpsyt.2022.910684. eCollection 2022.

Authors

Vincent Guinchat¹, Nicolas Ansermot², Kuntheavy Ing Lorenzini³, Dimitri Politis⁴, Youssef Daali³, Chin B Eap^{2

5

6

7}, Séverine Crettol²

Affiliations

¹ Psychiatric Section of Mental Development, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland.
² Unit of Pharmacogenetics and Clinical Psychopharmacology, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland.
³ Division of Clinical Pharmacology and Toxicology, Geneva University Hospitals, Geneva, Switzerland.
⁴ Addiction Medicine, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland.
⁵ School of Pharmaceutical Sciences, University of Lausanne, University of Geneva, Geneva, Switzerland.
⁶ Center for Research and Innovation in Clinical Pharmaceutical Sciences, University of Lausanne, Lausanne, Switzerland.
⁷ Institute of Pharmaceutical Sciences of Western Switzerland, University of Lausanne, University of Geneva, Geneva, Switzerland.

Abstract

Loperamide is an over-the-counter antidiarrheal for which increasing cases of abuse or misuse are described. We report the onset of opioid use disorder associated with low to moderate doses of loperamide in an intellectual disability patient without previous history of substance use disorder (SUD). Our patient presented strongly reduced activities of CYP3A and P-glycoprotein, which are mainly involved in loperamide metabolism and transport. We suggest that this led to an increase in bioavailability, systemic exposure, and brain penetration thus allowing loperamide to act on the central nervous system and contributing to the development of SUD. Slow release oral morphine (SROM) was chosen as opioid agonist treatment, which successfully contained loperamide use and globally improved her clinical condition. This situation highlights the need for caution and awareness when prescribing loperamide, particularly in vulnerable patients with few cognitive resources to understand the risks of self-medication and little insight into its effects.

Keywords: P-glycoprotein; case report; cytochrome P450; intellectual disability; loperamide; opioid use disorder.

Publication types

Case Reports