What's 'a safety blanket' in the following sentences.

Not everyone who gets the drug ends up taking it. There are some who die of natural causes and there are others who get it as a safety blanket.

Incidentally, I found them from an article dealing with euthanasia and assisted suicide.

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A safety blanket is a comfort object, such as a child's blanket that helps them feel safe or comfortable. In this context I assume it means they get the drug to reassure them that they can use it if they ever need to, but might not end up ever using the drug.

n.
1. a blanket carried by a child to provide reassurance.
2. any object that gives a feeling of security.

http://www.thefreedictionary.com/security+blanket
http://ja.m.wikipedia.org/wiki/%E5%AE%89%E5%BF%... - this may help but it doesn't go into a lot of detail and in this context maybe makes a little less sense.

Sorry if this doesn't help, to me it's not a common term "safety net" makes more sense for me. Hopefully the links help you find a better understanding!