Patients taking a common diuretic to help lower blood pressure may be better off with a similarly effective but safer one, a new study suggests.
Current guidelines recommend the drug chlorthalidone (Thalitone) as the first-line diuretic. But it can have serious side effects that can be avoided with another diuretic, hydrochlorothiazide (Hydrodiuril), researchers say.
“Diuretics are recognized as among the best drugs to treat hypertension, but there are no randomized studies to help decide which diuretic is best,” said lead author Dr. George Hripcsak, head of biomedical informatics at Columbia University in New York City.
Hydrochlorothiazide is the world’s most-used diuretic, but chlorthalidone is gaining favor because it is longer acting and, therefore, might be more effective, Hripcsak said.
Guidelines from both the American College of Cardiology and American Heart Association recommend chlorthalidone for that reason.
But the new study found that patients taking chlorthalidone were three times more likely than those taking hydrochlorothiazide to have dangerously low levels of potassium and other electrolyte imbalances, as well as kidney problems.
Six percent of patients taking chlorthalidone had low potassium, compared with 2% of those taking hydrochlorothiazide. The rate remained the same even with lower doses of chlorthalidone, the researchers found.
“If you are taking chlorthalidone, then your physician should be monitoring your electrolytes and kidney function carefully,” Hripcsak said.
For the study, his team reviewed 17 years of data on more than 730,000 patients treated for high blood pressure.
While both drugs were equally effective in preventing heart attack and hospitalization for heart failure and stroke, chlorthalidone had a higher risk of side effects, the study found. Those side effects include low potassium, which can trigger abnormal heart rhythms; low salt, which can cause confusion; kidney failure; and type 2 diabetes.
POTENTIAL SIDE EFFECTS OF OTHER COMMON DIABETES DRUGS:
Sulfonylureas: low blood sugar, upset stomach, skin rash or itching, weight gain
Biguanides/Metformin: sickness with alcohol, kidney complications, upset stomach, tiredness or dizziness, metal taste
Alpha-glucosidase inhibitors: gas, bloating and diarrhoea
Thiazolidinediones: weight gain, risk of liver disease, anaemia risk, swelling of legs or ankles,
Meglitinides: weight gain, low blood sugar
This is not the first study to point out these side effects of…