It's a balancing game - one of five factors. Lethality, pain, accessibility, gory aftermath (I personally don't pay mind to the gory aftermath, but it's important to many folks on here) and interruption risk. Interruption risk is especially important because most failed attempt stories I read from both on and off here are due to being interrupted by someone else. Also keep in mind - you yourself are an interruption factor if you freak out to the point where you call 911.
For instance - Official assisted Euthanasia covers 4 of these factors 100%, but accessibility is like... 5%. Not very accessible.
If you want something that is TRULY 100% lethal - becoming infected with Rabies. But it is a brutally painful and terrifying way to go. But there is no doctor that will be able to intervene if you are infected. It will end your life quicker than AIDS but again - very brutal.
Then there's the Gold Standard in CTB methods - Shotgun in the mouth. A high caliber bullet from a Magnum or equally powerful handgun works too. You can't beat death at the speed of sound. And even better - even if someone intervenes there's likely nothing they'll be able to do about it. The biggest problem is accessibility barriers - EVEN in the USA. We don't allow convicted felons to buy guns, and if you have any kind of mental disability, your status is basically that of a convicted felon. Ironically, our Mass Shooting problem over here has a lot more to do with how we treat our mentally disabled than our gun culture, but I'm getting completely off topic now.
HANGING - I'm a fan of hanging and it's the method I've chosen to go with when the time comes. Accessibility can't be beat - literally anyone can get a rope. As far as what to anchor that rope too - you have to make sure you have a solid anchor. Trees certainly work, as do railings. We have a lot of great threads on hanging tutorials here to make sure you have all the bases covered. The best thing about in my opinion is how you can essentially 'practice it' and test how it's going to feel before you fully commit to it. If you panic or find it too painful - you'll know before you commit that it's not the right method for you. Some people find they even LIKE the way it feels. Not uncommon. Look at David Carradine. I'd recommend reading the Japanese Suicide Handbook on hanging. And any method really, it's a very informative book.
JUMPING - Jumping from a high enough height onto solid ground is 100% lethal. Bridges are a bit more finicky. If you jump from the roof of a 30 story building (provided there isn't a bunch of assholes at the bottom waiting with one of those rescue tarps) you will simply not survive. HOWEVER - SI is going to kick in hardcore with this one. It might take an hour on that ledge to will yourself to jump, and in that time, if you're seen and the authorities are called...it's not gonna be good.
SN - I feel I'm in the minority on this board on this subject, but I just don't like SN. It's not like Cyanide where it's 100% lethal no matter what (though Cyanide is far more painful), and I don't think it's as peaceful as we think. I feel like if you're going to go with a method where a moderate amount of pain is involved - I would go with hanging because the hard cap on the amount of time that pain will last is 3-4 minutes. The pain of SN will last at least 45 minutes to an hour, and unlike other poisons, SN is survivable.
FENTANYL - I mean, it's such a deadly substance we're starting to use it in executions here in the US. If you're going to go out via a poisonous substance, a Fentanyl OD is the ever coveted "everything just goes black and you die" painless death. Of course, it's illegal and authorities carry around a drug whose sole purpose is to be a Fentanyl antidote (Narcan).
I could go on and on, but these are the methods I have the most knowledge about. Like I said earlier, I'd recommend reading the Japanese Suicide Handbook which can be found here:
https://archive.org/details/the-com...edited-by-google-and-myself-wataru../mode/2up
As well as this breakdown of methods by time, lethality, and pain (though I feel some of these numbers can be disputed)
For information on the most lethal methods of suicide, a good starting point is the statistics on the number of successful suicides by method (see Suicide statistics). There is also a much published study from 19951, where 291 lay persons and 10 forensic pathologists rated the lethality, time...
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