Hello and thank you for the opportunity to help in answering your question. Based on the information that you've provided it sounds as though you are experiencing "anticipatory anxiety" essentially meaning that you grown into an anxiety or panic attack just based on anticipating driving and having an irrational unjustified fear that you will black out.
My first suggestion would be for you to consider seeing a therapist to help you work through the anxiety; specifically one that is experienced in Cognitive Behavioral Therapy as this is the most effective form of treatment for this condition. It helps you to explore further your thoughts and the resulting impact that they have on your emotional state thus resulting in the anxiety. You will also be provided with different ways of coping such as breathing retraining which helps to lower your heart rate and uncloud of your thoughts and judgment thereby giving you the ability to cope better with the stress and anxiety.
I would also like to suggest a workbook that is based precisely on the above mentioned and that you can do on your own time. The workbook also includes specific exercises mentioned above as well as ways to help you cope better with and manage better than anxiety and panic.
Here is a link to the workbook:
Finally, I would suggest that you consider seeing your physician and consider taking Klonopin 1-2 mg per day which is an anti-anxiety and help you manage better thereby allowing you to implement therapeutic approach mentioned above better. The reason that the benranol isn't working as well as you would like is because it is a beta blocker and they are considered to be more for maintenance as opposed to treating acute episodes as the ones you've mentioned having. Furthermore, these medication properties are not as strong as the anti anxiety medications I mentioned above.
I hope that I have been helpful in answering your question and that you found my suggestions to be of benefit to you.
Please let me know if you have any further questions that I can help in answering for you. I want to be certain that I have answered your question completely and thoroughly.
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