Beta amyloid (plaques) have not been proven to be the CAUSE of dementia in Alzheimer's. Celexa, one SSRI, was indeed shown to reduce CSF levels of beta amyloid, which *sounds* good. The only problem is that in elderly dementia patients with agitation, an RCT of Celexa had to be stopped early due to increased arrhythmia and worsened cognition as measured by the MMSE.

Vaccine trials utilizing new drugs did indeed show them to effectively "mop up" beta amyloid plaques, but there was no improvement in actual dementia. Time to abandon this failed theory, along with the decreasing utility of dangerous SSRI drugs that already don't do much for their approved uses and come with tremendous risks, including falls, fractures, hemorrhagic stroke, possibly diabetes, and akathisia (an agitated dysphoric state implicated in violence and suicide).