Date of report 27 Feb 2020
Reported case interaction between
Darunavir and Psyllium
Darunavir and Psyllium
Drugs suspected to be involved in the DDI
Complete list of drugs taken by the patient
Gunabasic, lipidum
Clinical case description
HIV patient experiencing virologic rebound (mean HIV RNA: 80 copies/mL) after starting using two CAMs a few weeks before. Gunabasic, which is a taraxacum‐containing dietary supplement claimed to be a draining agent; and Lipidyum, which is a dietary supplement of phytosterols (mainly psyllium) recommended as a nonpharmacological approach to constipation, hypercholesterolemia, and overweight. The patient was enrolled in a clinical trial aimed at assessing the efficacy of a once‐daily fixed‐dose formulation containing tenofovir alafenamide, emtricitabine, darunavir, and cobicistat; no TDM data were available. Remarkably, HIV viral load, assessed a few weeks after discontinuation of the weight‐loss agents, returned to < 37 copies/mL. This case has been published by Cattaneo D, et al. in Obesity (Silver Spring). 2018 Aug;26(8):1251-1252.
Clinical Outcome
Drug Interaction Probability Scale (DIPS)
Editorial Comment
Weight-loss drugs should be used with caution in HIV-infected patients treated with antiretroviral drugs because of the risk of virologic failure. This episode could be related to psyllium, a soluble fiber from the husks of Plantago ovata that is able to increase stool weight and promote laxation; and is reported to decrease the absorption of calcium (Heaney RP, Weaver CM. Effect of psyllium on absorption of co‐ingested calcium. J Am Geriatr Soc 1995; 43: 261‐ 263)
University of Liverpool Recommendation
No clinically significant interaction expected