according to livestrong.org, "the approximate lethal dose of 90 to 100 percent isopropanol for human adults is only 250 milliliters, or about 8 ounces." eight ounces. to put it in perspective: the average shot glass is 1.5 ounces. a can of coke is 12 ounces. ingesting only eight ounces of rubbing alcohol can kill you.