Not the only one, heavier (not as in heavier than xenon,...
User FW900, in the DrugNerds subreddit,
Not the only one, heavier (not as in heavier than xenon, just heavier noble gasses) argon and krypton also show similar activity…
The diverse biological properties of the chemically inert noble gases
Overview of attention for article published in Pharmacology & Therapeutics, February 2016