Clinical trials may involve risk, as can routine medical care and the activities of daily living. When weighing the risks of research, you can think about these important factors:

  • the possible harms that could result from taking part in the study
  • the level of harm
  • the chance of any harm occurring

Most clinical trials pose the risk of minor discomfort, which lasts only a short time. However, some study participants experience complications that require medical attention. In rare cases, participants have been seriously injured or have died of complications resulting from their participation in trials of experimental treatments.

The specific risks associated with a research protocol are described in detail in the informed consent document, which participants are asked to consider and sign before participating in research. Also, a member of the research team will explain the study and answer any questions about the study. Before deciding to participate, carefully consider risks and possible benefits.

Potential benefits

Well-designed and well-executed clinical trials provide the best approach for you to:

  • help others by contributing to knowledge about new treatments or procedures
  • gain access to new research treatments before they are widely available
  • receive regular and careful medical attention from a research team that includes doctors and other health professionals


Risks to taking part in clinical trials include the following:

  • There may be unpleasant, serious, or even life-threatening effects of experimental treatment.
  • The study may require more time and attention than standard treatment would, including visits to the study site, more blood tests, more procedures, hospital stays, or complex dosage schedules.

Reproduced with permission from NIH Clinical Trials and You. NIH does not endorse or recommend any products, services, or information described or offered here by Healthline. Page last reviewed on October 20, 2017.