Anxiety may be related to many things, so it's best to figure out what exactly is stressing you and avoid it or try to detach from it as much as you possibly can. Which may or may not be possible. There's also karmic issues that can tie into this.
Anxiety and other mental disorders go away on their own when you start meditating consistently on a daily basis as well as performing Hatha Yoga. As most of these are a result of low bioelectricity anyway. It can also be related to negative energies from people around you, as well as people who actually drain you on top of that. It's very important to clean your aura and chakras daily (minimum twice a day) as well as building a strong aura of protection around you.
Void meditation goes a long way here, as well as practicing awareness and consciousness to detach from unwanted and useless feelings and emotions. You might also want to close your chakras when near negative people. It may be hard at the beginning and seemingly impossible to control, but with discipline and determination you can take full control of your own mind. And permanently get rid of anxiety and other mental disorders that might be related to it.
Lastly, you can go through the
Runes page and figure out which one you want to use to fix whatever is behind the anxiety, which also helps a great deal, say you feel anxious because of your financial situation you may want to work with Fehu, if you feel anxious because you are low on energy, work with Sowilo for a boost, Algiz for protection, and so on, you get the point. For a generalized working Wunjo and/or Nauthiz works well. It worked for me. But again, it is individual, as my situation was related to the affairs ruled by these runes. So you may ask yourself what's making you feel that way in the first place and work your way from there.