Dictionary of Cancer Terms
View in Spanish: Fenómeno adverso
Adverse event (AD-vers eh-VENT)
An unexpected
medical problem that happens during treatment with a drug
or other therapy.
Adverse events do not
have to be caused by the drug or therapy, and they may be
mild, moderate, or severe. Also called adverse effect.
Source: National Cancer Institute Dictionary of Cancer Terms, available at www.cancer.gov/dictionary.