Imaging and other tests

Before starting lecanemab or donanemab, you need a test to determine the presence of brain amyloid. Most commonly this test is either an amyloid PET scan or a test of cerebral spinal fluid to measure levels of beta-amyloid in the brain. MRI scans are needed to monitor for brain swelling or bleeding. After starting lecanemab, MRI is recommended before the fifth, seventh and 14th IV treatments and after one year of treatment. After starting donanemab, MRI is recommended before the second, third, fourth and seventh IV treatments.

Your care team watches for side effects and asks you or your caregiver how your body reacts to the medicine.