>> competently choose to do so.
At least with Alzheimer's, there is no bright line between competence and incompetence. It's a relatively slow slide into incompetence. And not an even progression, since in fuzzy area there may be periods of competence mixed with periods of incompetence. I think big part of problem for person with Alzheimer's to make decision of suicide is to have the resolve to do it early enough, while they're still clearly competent and would have much more time as a competent person, instead of waiting to try and milk out as much time as they can. Cause if you wait you're likely to forget your strong desire (I'm not joking here) or simply lack the resolve to do the deed.
>> I would want to do so with quick and painless drugs
>> instead of a gun. However, assisted suicide is only
>> legal in a handful of US states, and then only in
>> cases of terminal illness with less than six
>> months to live.
I'm not sure why, but you seem to think use of "quick and painless drugs" requires use of assisted suicide. Maybe one solution would be for someone to publish some "How To" information on how to assemble and use a quick and painless drug solution, all on your own. Then at least anyone worried enough about developing Alzheimer's would have a length of time measuring in years to get their solo-suicide plan in place.
I say this as a person who hopes he'd be able to take his own life before incompetence comes. My father and several members of my extended family had Alzheimer's. I think that people who lack experience with it are sometimes unaware of how Alzheimer's robs a person of their personhood. It's not pretty and nobody should ever have to go through it.