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Patient Recruitment

Do You or Someone You Know Have Sickle Cell Disease?

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Researchers at the National Heart, Lung, and Blood Institute in Bethesda, Maryland are conducting a study to evaluate the effects of a natural supplement (Isoquercetin) on the markers reflecting blood clotting risk. The risk of blood clotting (thrombosis) is higher in people with sickle cell disease (SCD). Thrombosis puts people with SCD at significant risk for heart and lung problems. Treatment for thrombosis with blood thinners can increase the risk of bleeding. This study will evaluate an agent that acts like a blood thinner but does not appear to have any bleeding risk.

Study Design:

  • This is a double blinded study, where the participant will be assigned to 1 of 2 groups to receive either the study supplement (Isoquercetin), or a placebo (sugar pill)
  • Participants will be asked to take Isoquercetin or a placebo, daily for 4 weeks
  • Blood samples will be collected
  • There are no costs for study-related tests and drug
  • Compensation for participation will be provided

To Participate, you:

  • Must be 18 or older
  • Must have sickle cell disease

The NIH Clinical Center, America's Research Hospital, is located in Bethesda, MD. On the Metro red line (Medical Center stop).

For more information:
NIH Clinical Center
Office of Patient Recruitment
800-877-8339 (TTY / ASCII)
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Or go online:
Refer to study # 20-H-0137

Department of Health and Human Services
National Institutes of Health Clinical Center (CC)
National Heart, Lung, and Blood Institute (NHLBI)

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This page last updated on 10/22/2021

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