Ah, I think I understand what you're trying to say ... the propanolol is causing the asthma flares, not the tremors. I'm sorry that you're dealing with anxiety and all the miserable physical symptoms that can come with it. You're not alone. I and many others here have gone through similar issues.
Have you been given anything besides propanolol for your anxiety in the past? There are many options, including antidepressants (certain ones can also be used to manage anxiety) and anti-anxiety medications like benzodiazepines (Prozac, Zoloft, Xanax, etc). It's also a good idea to consider therapy, so that you can learn effective coping skills while also having a space to talk through your concerns. Generally, people who use both therapy and medication together tend to have stronger outcomes than those who just do one or the other.
Everyone is different, so we can't say exactly what medication would be best for you. The best person to help you with that would be your doctor.
I hope some of that information is useful and that you can find some relief. Anxiety feels all-consuming but you really can recover. Sending hugs to you. Please keep us posted. -Melissa, team member