From Dignified Dying 2006 (page 85);
We are informed by reliable sources that it is common practice for patients to take anti-emetic medications only 1 hour prior to h the barbiturate. In Chapter 2.2.8 we recommend that one begins using anti-emetics at least 36 hours before carrying out a humane self-chosen death.
Regurgitation has been reported in 12 (5%) of the 246 cases. wozz believes this complication would be reduced with an earlier start ofthe use ofanti-emetic medication.
https://www.dignifieddying.com/publicaties/EN/2006 Guide to Self-Chosen and Humane Death.pdf
However, they changed to 24 hours in the dutch 2008 edition of Dignified Dying (page 107 - I translate);
It seems that patients usually take an anti-emetic agent just one hour before taking the barbiturates. We advise you to start at least 24 hours in advance. Regurgitation with the patient was reported in 12 (5%) of the 246 cases. Possibly this would occur less frequently if an anti-emetic agent was to be started earlier. https://dignifieddying.com/publicaties/NL/2008 NL Guide to a Self-Chosen and Humane Death.pdf
My end-of-life counselor (who's keeping an entire database of N takers - asking family to report back how it went etc.) was clear as well with a total of 5 tablets;
- 25 hours (before..) 2 tablets
- 8 hours after that ^ 1 tablet
- 8 hours after that ^ 1 tablet
- 8 hours after ^ 1 tablet (< that's 1 hour before the final step)