The diuretic chlorthalidone, a mainstay in blood pressure management, is prone to more serious side effects than another diuretic, hydrochlorothiazide, which is just as effective, a recent study reported.
Chlorthalidone is the preferred diuretic for high blood pressure, according to treatment guidelines. But in the new study, published inJAMA Internal Medicine in February 2020, the researchers found that 6 percent of people taking chlorthalidone experience low blood potassium (hypokalemia), compared with 2 percent of patients taking hydrochlorothiazide.
Patients also have a similar risk of electrolyte imbalances, which can cause abnormal heart rhythms; kidney failure; low sodium (hyponatremia), which can cause confusion; and type 2 diabetes. Still, the study was based on observational data that can’t prove a direct link between the diuretic and the side effects; more robust studies are needed.
Until then, consider asking your doctor if he or she should be monitoring your electrolyte levels and kidney function if you’re taking chlorthalidone.
This article first appeared in the April 2020 issue of UC Berkeley Health After 50.
Also see Blood Pressure Meds: Best at Night.