This drug is more commonly known here in the USA as Entyvio. You might want to edit your thread title to do an a/k/a in the thread title, in order to get more responses from recognition of the term. There are people on the board using Entyvio.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .