Can taking a high amount of benzodiazapines and over a long period of time give you alzheimer's or amnesia of some sort?

yes: Memory problems is a classic collateral effect, very common after using this drugs. Loss of balance, dependency, and depression are also frequently observed. Not alzheimers. Bad idea for the long term; read the insert that pharmacy gives you, and you will notice that even manufacturers warn you and clarify that no studies demonstrate efficacy beyond a period of time, and all. Ask your dr.Good luck.

Yes: There are several studies showing that use of benzodiazepines increases the incidence of dementia.