It all started when a Twitter user wrote, "I made some hand sanitizer out (of) your vodka. The hand sanitizer doesn't taste bad either. Cheers to Tito's vodka. Keeping me germ-free and feeling good at the same time." and Tito's responded by saying,
"Per the CDC, hand sanitizer needs to contain at least 60% alcohol," Tito's Handmade Vodka tweeted on Thursday. "Tito's Handmade Vodka is 40% alcohol, and therefore does not meet the current recommendation of the CDC."
The company was replying to a user who bragged about using the vodka to make a DIY hand sanitizer.
More about the warning here.