While Dimenhydrinate is readily available, it can occasionally give rise to a number of unpleasant (anti-cholinergic) side effects.
Note - This drug readily crosses into the brain. In larger doses, it can cause distortions in sight, sound, and perception, even confusion and amnesia. For this reason a prior test-dose is recommended.
Unless there are specific questions of hypersensitivity, allergy or evidence of significant side-effects, the anti-emetic meto- clopramide is the recommended end of life anti-emetic. The suggested dose for metoclopramide is independent of the type or quantity of the lethal drug to be used. That is, the dose is independent of whether the drug is to be taken as a ‘stat dose’ (30mg at the same time) or over a continuous 48-hour period (10mg 3x/day for 2 days).
If significant neurological side effects are noticed with meto- clopramide, it is advised to switch to Domperidone or Ondan- setron (Zofran).
To obtain some of these anti-emetic drugs, a prescription is necessary, so be prepared to tell a story to your doctor. Resons for needing an anti-emetic might include a planned sea cruise. If you provide the real reason - that you need an anti-emetic so as not to vomit up your end of life drugs - you will be unlikely to get a positive response!
If problems of access do develop and you find yourself unable to get metoclopramide, why not settle for over-the-counter Dramamine, or some good quality cannabis!