Hello i know someone whos has cancer he wants to die hes taking 250 sominex which is diphenhydramine he also wants to use helium?

Get the facts: As a pathologist, i've run into two completed suicides in which the person believed they had cancer but actually did not -- they had a manageable illness. Most terminal cancer can be managed by hospice and the barbarous cruelty of past decades is over in most jurisdictions. You can take away the pills, call 911, or phone the person's physician as applicable. At least phone hospice for him.

250 pills?: Has he met with spiritual/ emotional counselor? My concern is that if he has depression, that could be pushing him toward that decision - vice his normal judgment. Is he in severe pain? If yes, his pain should be addressed. Does he have a support system? Is he aware of other options? Some times people aren't aware of them.