Ashwagandha is a natural beta blocker, and will help support the adrenals also helping to prevent excess epinephrine.
Jiaogulan will also help strengthen the adrenals reducing epinephrine release. Jiaogulan is also the highest herbal source of sterols that I am aware of. Sterols help to relax blood vessels lowering blood pressure. They are also great for lowering cholesterol.
Also get to the doctor early so he has time to sit and relax. Have him sit there and take some slow deep breaths and have him exhale slowly through his nose. Doing this 3-4 times will help relax him.