I think Propranolol is a wonder drug. I have had terrible panic attacks in the past when doing public speaking to the point that my heart would be so fast that I could no longer continue speaking and would have to stop the presentation....talk about embarrassing. My recommendation is for you to try 40 mg of propranolol next time. That should be strong enough to get you through a presentation. I googled Etifoxine (had never heard of it before), and apparently it's not FDA approved which I found interesting.
So for me, propranolol was really great, because it slows your heart rate down, meaning that I wasn't able to go into a full blown panic attack. As long as my heart rate doesn't go up, I feel completely fine to give a presentation.
In cognitive behavioral therapy, they teach you that thoughts, emotions/feelings and behavior fit together like a triangle. If you can start to work on one 'point' of this triangle, it will start to help the other two. Because my feelings sometimes would become so overpowering (like the racing heart beat), I always thought it was amazing that it just took this one drug to stop the physical symptom (feeling) of a fast heart beat, and that in turn shut down the panic attack. Just wish I could fix a lot of my negative thoughts and self talk :(