Date of report: 22 Jun 2020
Reported case interaction between
Cobicistat and Alprazolam
Cobicistat and Alprazolam

Drugs suspected to be involved in the DDI
Drug A
Cobicistat
(Perpetrator)
Daily Dose
150
(mg)
Dose adjustment performed
No
Administration Route
Oral
Start date
Nov. 14, 2018
End date
Ongoing
Drug B
Alprazolam
(Victim)
Daily Dose
1.5
(mg)
Dose adjustment performed
Yes
Administration Route
Oral
Start date
Sept. 17, 2019
End date
Ongoing
Complete list of drugs taken by the patient
Antiretroviral treatment
Darunavir/Cobicistat
Efavirenz/Emtricitabine/Tenofovir-DF
Complete list of all comedications taken by the patient, included that involved in the DDI
Alprazolam
Clinical case description
Gender
Male
Age
27
eGFR (mL/min)
>60
Liver function impairment
No
Description
27 year-old, MSM. HIV infection diagnosed in 2014. Currently on cART with darunavir/cobicistat plus emtricitabine/tenofovir. Last HIV RNA pVL 20 copies/ml in October 2019. The patient uses different substances including mephedrone, alcohol and poppers occasionally. In September 2019 he had panic attach. He was admitted at the psychiatric clinic and alprazolam tablets 0.5 mg 3 times daily were prescribed. A few weeks later he felt with no energy, sedated and he referred having problems with movement and memory, which again affected his work. Alprazolam dose was reduced to 0.25 mg 3 times per day, and the patient was discouraged for drinking alcohol. Soon after, the patient did not complain about any side effect of alprazolam and he was able to work normally.
Outcome
Toxicity
Drug Interaction Probability Scale (DIPS)
Score
4 - Possible
Editorial Comment
Alprazolam is mainly metabolized by CYP3A4. Coadministration of darunavir/cobicistat may increase alprazolam concentrations and may result in enhanced sedation. As in this case, decrease in alprazolam dose may be needed.