THC could be a good treatment option, attacking Alzheimer's disease in multiple ways.

The first study, titled The Potential Therapeutic Effects of THC on Alzheimer's Disease was published in 2014 and got little fanfare. This study is behind a paywall, but you can read the abstract details at the link above. Hopefully, the information presented here will be enough to help you decide whether you should study this more thoroughly.

What Causes Alzheimer's Disease?
Alzheimer's disease is a neurodegenerative disease that is believed to be caused by the accumulation of amyloid proteins, which cause nerve cell death.

The build-up of these proteins triggers a toxic inflammatory response that begins the process and eventually leads to brain and nerve cell death. Currently, there are no drugs that significantly affect this process.