(RxWiki News) Although it's the most prescribed blood-pressure medicine on the market, hydrochlorothiazide, a diuretic (or "water pill"), is much less effective than common hypertensive treatments.
Lead researcher Dr. Franz Messerli, who heads the hypertension program at St. Luke's-Roosevelt Hospital in New York, said that by prescribing hydrochlorothiazide, patients and physicians are given a false sense of security because, based on a new meta-analysis, the medication is not as effective as other treatments, such as angiotensin-converting enzyme (ACE) inhibitors and beta blockers.
Messerli and cohorts reviewed 19 studies comparing hydrochlorothiazide to other drugs in randomized trials and found low doses of hydrochlorothiazide reduced systolic ("top") blood pressure by 6.5 points, compared to 12.9 points for ACE inhibitors, 11.2 points for beta blockers and 11 points for calcium-channel blockers, on average. (Blood pressure systolic readings for 140 mmHg and over are considered high.)
Physicians wrote 134 million hydrochlorothiazide prescriptions in 2008 alone, many times the number of prescriptions for the second-most commonly prescribed blood pressure medicine, atenolol, a beta blocker.
Hydrochlorothiazide, which belongs to a class of drugs known as thiazides, appears more effective in higher doses, but side effects, including blood sugar and insulin problems, complicates higher-dosage prescriptions.
The drug appears to not work as well at night, and nighttime and early-morning blood pressure readings are particularly important risk factors for heart attack and stroke, Messerli said.
The finding does not extend to other thiazides such as chlorthalidone or indapamide.
In addition to medication, lifestyle factors play a big role in the successful management of blood pressure, including a low-sodium, low-fat diet, plenty of exercise and not smoking.