HCQ interactions

 Q: Hydroxychloroquine (HCQ) ________ the digoxin level? (select one)

A) increases 

B) decreases

Answer: A

Since HCQ is again popular, the objective of the above question is to highlight the significant and sometimes fatal interaction of HCQ with many important drugs that are used in an inpatient setting. QTc prolongation is well known with many medications and has been discussed well recently in literature with deaths during COVID pandemic (the list can be found somewhere else).

Inpatient hypoglycemia is also a concern when HCQ is used with antidiabetics. In transplant patients, HCQ can increase cyclosporine levels and in cardiac patients, digoxin levels.

#pharmacology

References:

1. Nampoory MR, Nessim J, Gupta RK, Johny KV. Drug interaction of chloroquine with ciclosporin. Nephron 1992; 62:108. 

2. Finielz P, Gendoo Z, Chuet C, Guiserix J. Interaction between cyclosporin and chloroquine. Nephron 1993; 65:333. 

3. Leden I. Digoxin-hydroxychloroquine interaction? Acta Med Scand 1982; 211:411.

4. Chloroquine phosphate USP prescribing information (October 2018) available at US National Library of Medicine DailyMed website available at https://dailymed.nlm.nih.gov/dailymed/getFile.cfm?setid=06c69e2b-211b-4746-9f3a-f86d36520570&type=pdf&name=06c69e2b-211b-4746-9f3a-f86d36520570 (Accessed on September 26, 2020).