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Treating hypertension with time-released garlic tablets

Researchers from the Russian Academy of Natural Sciences, in Moscow report that time-released tablets (Allicor) are more effective than regular garlic supplements (Kwai).

First, the details.

  • 84 men with mild or moderate high blood pressure were randomly assigned to treatment groups.
  • First, 600 mg Allicor vs. placebo daily for 8 weeks.
  • Neither patients nor researchers knew the treatment — double blind.
  • Then, 2400 mg Allicor daily vs. 900 mg Kwai daily.
  • During this treatment, the patients and researchers knew their treatment.

And, the results.

  • Allicor significantly reduced systolic and diastolic blood pressures by 7 mm Hg and 4 mm Hg, respectively.
  • Increasing the Allicor dose to 2400 mg daily did not provide any added benefit.
  • Treatment with Kwai resulted in the same decrease in systolic blood pressure as Allicor, but didn’t decrease in diastolic blood pressure.

The bottom line?
“The results of this study show that time-released garlic powder tablets are more effective for the treatment of mild and moderate arterial hypertension than are regular garlic supplements,” concluded the authors.

The authors speculate, “Different effects of Allicor and Kwai on diastolic blood pressure may be because of the prolonged action of Allicor.” They hypothesize that more of the vasoactive constituents of the time-released garlic powder are available to act on blood vessels.

Maybe so. But reviewers from Hartford Hospital in Connecticut recently reported, “The effect of garlic preparations on systolic and diastolic blood pressures are comparable to the hypotensive effects of commonly-prescribed blood pressure drugs.”

Unlike the patients treated in Moscow, the Hartford reviewers found that garlic reduced diastolic blood pressure by 9 mmHg vs. 4 mmHg with the garlic used in the Russian study. It was also associated a greater reduction in systolic blood pressure — 16 mmHg vs. 9 mmHg in the Russian study.

Are these differences due to a less potent garlic product?

In 2006, tests by found that 8 of 18 garlic supplements failed their quality control analysis. One product lacked any of a key garlic compound, and another had less than 1% of the expected amount of this compound. Other products claiming “high potency” were actually low potency. Two products were contaminated with lead.

Whether the Russian researchers pretested their drugs for potency isn’t stated in the abstract.

4/26/09 21:30 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.