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Government Funding Lapse
Because of a lapse in government funding, the information on this website may not be up to date, transactions submitted via the website may not be processed, and the agency may not be able to respond to inquiries until appropriations are enacted.

The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit cc.nih.gov.

Updates regarding government operating status and resumption of normal operations can be found at opm.gov.

adverse reaction

(AD-vers ree-AK-shun)
An undesired effect of a drug or other type of treatment, such as surgery. Adverse reactions can range from mild to severe and can be life-threatening. Also called adverse effect and adverse event.
Search NCI's Dictionary of Cancer Terms