Health Information and Clinical Trials

Get science-based, plain-language information related to heart, lung, blood, and sleep disorders from the NHLBI.

Information about specific heart, lung, blood, and sleep disorders can be found in our online science-based, plain language Health Topics articles. The A to Z index on this webpage should help you find articles on diseases, conditions, tests, procedures, and other relevant topics, which you can print and share.

How can I be sure of the quality of information provided by NHLBI?

How can I download or order NHLBI publications and materials?

Can the NHLBI give me advice about a specific medical condition, provide me with a second medical opinion, or recommend medical specialists or hospitals in my area?

The NHLBI does not give medical advice, render second opinions, provide referrals to doctors, or counsel individuals on specific medical problems. Advice on treatment or care of an individual patient should be obtained through consultation with a physician or other health professional who has examined the patient and is familiar with the patient's medical history.

Can I receive medical treatment at the NHLBI?

The NHLBI is a biomedical research organization. As such, the NHLBI only enrolls patients who are participating in NHLBI clinical research studies. These studies span a wide range of diseases and conditions. More information on clinical trials can be found on the NHLBI and NIH websites.

What are clinical trials?

Where can I find information about children and clinical studies?

Where can I find information about National Institutes of Health (NIH) clinical research trials?

How do I find patient recruitment information for studies being done by the NHLBI?

Where can I find publicly and privately supported clinical studies conducted around the world?

What is ResearchMatch?

Can I volunteer for clinical research studies even if I am healthy?

The NIH Clinical Center provides an opportunity for healthy volunteers to participate in medical research studies (sometimes called protocols or trials). Healthy volunteers provide researchers with important information for comparison with people who have specific illnesses. Every year, nearly 3,500 healthy volunteers participate in studies at the NIH. If you are interested in volunteering for an NHLBI study, the NIH Office of Patient Recruitment, ( can help you.

Still can't find what you're looking for?

Contact the NHLBI Center for Health Information at or 301-592-8573. Open Monday through Friday, 8:30 a.m. to 5 p.m. Eastern time (closed on Federal holidays). After hours, you may leave a voicemail message or send an email, and your inquiry will be answered the next business day.


For access to free Telecommunications Relay Services (TRS), dial 7-1-1 on your telephone.

Postal Mail

NHLBI Center for Health Information
P.O. Box 30105
Bethesda, MD 20824-0105
United States