Breast Implant Illness (BII)

Breast implant illness, or BII, is not an official medical diagnosis. The FDA says patients and clinicians use the term to describe a variety of systemic symptoms reported after breast reconstruction or augmentation, including fatigue and problems with memory or concentration ("brain fog"). Other reported symptoms include joint and muscle pain, anxiety, depression, hair loss, rashes, and sleep problems.

The FDA has been collecting reports. In its review of medical device reports from January 1, 2008 through June 30, 2024, the FDA identified 10,318 reports describing systemic symptoms in people with breast implants; fatigue was the most common, appearing in 41.1% of them. Because these reports are voluntary and incomplete, they do not prove implants caused the symptoms, and research is ongoing. Some people report improvement after implant removal, but not everyone does.

BII is different from BIA-ALCL, a rare lymphoma linked mainly to textured implants, which is a defined cancer with clear diagnostic tests. That difference matters legally. BIA-ALCL claims rest on a diagnosis that pathology can confirm, while BII claims face a harder causation question because there is no single test and the symptoms have many possible causes.

If you have implants and new symptoms, see your doctor and keep your implant card, which lists the manufacturer and model. See our breast implant cancer lawsuit page and our term page on textured breast implants.