Don't worry, it's bitter but it's harmless! Totally edible, just unpleasant. It also lasts longer than most drugstore habit-breaking polishes — and works to stop kids from sucking their thumbs!
Promising review: "This stuff is amazing. I've been a terrible nail-biter since I was a young child, and I tried everything to stop. I hated my hands and was so ashamed of how they looked, but I couldn't help it. I tried rubber bands, mindfulness meditation, Pavlov, and all sorts of other 'no bite' polishes that looked awful and washed off too quickly/didn't taste bad enough to be a deterrent. I committed to putting a layer of this on every other day, and it's now been three months and my nails look amazing. The urge to bite has lessened, but I don't think it will ever go away, so I plan to use this polish for years to come. The taste is so strong and immediately bitter, and it really lingers on your lips and tongue for a while. It's an amazing product, and I highly recommend it." —Lydia G Morgan
Get it from Amazon for $15.50.
To learn more about why people swear by this, check out "This Miracle Polish Just Might Get You To Stop Biting Your Nails".