This is from "Guide to a Humane Self-Chosen Death". Most actual data I have found here and elsewhere though, is about doses that range from 9g to 15g. Given the recent survivor thread, it's definitely confirmation that you really need to not be found for a while to be absolutely sure. Them still being rescued after 22 hours was concerning but they were almost double my weight and I believe they never specified if they abused pills and/or alcohol, only that they did not do drugs.
The dosage rabbit hole is a torturous one to fall into, if you are able to get 2, get 2 so that you aren't constantly on edge because of doubt. But I
personally believe (keep in mind I am no doctor) that 1 will work if there is no medical intervention for some days. I'll be booking a room for 2-3 days, if it doesn't work I will definitely come back here to report on it.
Someone also had a test done and supposedly there was more than 63mg/mL in their bottle, somewhere in the 70s, But, that was just a single person. Maybe all bottles have more than advertised, or maybe that was a one-off. Who knows, I'm just going to assume it was a one-off.