The drug, Vizamyl, is an injection of radioactive material designed to highlight abnormal brain plaque in medical imaging scans.
Dementia caused by Alzheimer’s is associated with buildup of the plaque, known as beta amyloid protein. However, it can also be found in patients who do not have neurological problems.
Vizamyl works by binding to the plaque and creating images that show up on positron emission tomography, or PET, scans of the brain.
The FDA says a negative scan means there is little plaque and the cause of dementia is probably not Alzheimer’s. A positive scan means the patient has at least some plaque, but does not prove they have Alzheimer’s.