i don't see the point in IVing etizolam but long term side effects: you may grow man titties, you will become dependent, possibly addicted as well, cognitive deficits are still debated but etizolam in general seems less prone to mental fog than traditional benzodiazepines.
Other than that we have the eye twitching issue and basically the same long term effects that benzos have. In terms of brain damage or cognitive impairment, well i think the jury is still out on whether benzos themselves cause either, especially permanently. I think it's safe to say your memory will be messed up while on benzos/etizolam and your ability to form new memories will be impacted but if you're only taking therapeutic doses this isn't an issue. If you are abusing etizolam then it's a sure thing but upon cessation of etizolam, your memory should go back to normal.
Go through the research and make a decision, last time i checked there were solid arguments on both sides that benzos would cause/not cause damage. Etizolam is a bit easier on the body IME (and i've had a fair amount) but that doesn't speak to its possible dangers in the long term. I'm sure places where it is legal have had long term studies done that you can look at.