Would swallowing Astring-O-Sol kill?

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I'm wondering if swallowing undiluted/concentrated Astring-O-Sol is lethal. I have no plans on trying it and I read the back of the bottle and it doesn't have any warning pertaining to swallowing. All I know that it hurts when you rinse your mouth with too much Astring-O-Sol, but I don't know if it's deadly.