Date of report 04 Jul 2024
Reported case interaction between
Lopinavir/ritonavir and TERFENADINE
Lopinavir/ritonavir and TERFENADINE
![FLS Science](/static/pictures/doctor-desktop.png)
Drugs suspected to be involved in the DDI
Complete list of drugs taken by the patient
Terfenadine 60 mg 3x/day, prednisone 30 mg/day,
Clinical case description
A 38-year-old female on long-term antiretroviral treatment with lopinavir/r + lamivudine + TDF presented a loss of consciousness and convulsion during her sleep. She was admitted to the emergency department. The heart monitoring showed ventricular fibrillation which was resolved with defibrillation, restoring her consciousness. She reported being prescribed terfenadine and prednisone for urticaria. After 3 days on this medication, she suddenly lost her consciousness and presented alterations of the electrocardiogram characterized by QT prolongation and torsade pointes which occurred several times for a period of 2 days. This clinical presentation was attributed to the interaction between lopinavir/ritonavir and terfenadine. Ritonavir strongly inhibits CYP3A4 which is the main enzyme metabolizing terfenadine.
This case was published by Mu X et al. Front Pharmacol 2023.
Clinical Outcome
Drug Interaction Probability Scale (DIPS)
Editorial Comment
University of Liverpool Recommendation
![](/static/img/key-simbols/red.png)