Black licorice is great! And that man is going to kill someone!
When I have a patient present with low potassium, cardiac rhythm issues, high blood pressure, swelling of the extremities and/or heart failure I always ask if they have been eating licorice. In 40 plus years I’ve never had a positive answer, but glycyrrhizin can cause these issues via it’s action on the kidneys.
Cases are well documented in the medical literature. Adverse effects have been reported on people who have eaten as little as 2 oz/day for over 2 weeks. These effects can be compounded in patients taking other medications.