The best treatments for anxiety related to stress are relaxation methods like deep abdominal breathing and meditation.

To practice deep abdominal breathing:

• Place one hand on your abdomen, directly beneath your rib cage
• Inhale slowly and deeply through your nose, filling the bottom of your lungs. Your chest should move only slightly, as your stomach expands, pushing your hand up.
• After you’ve inhaled fully, pause for a moment, then exhale fully through your mouth. Purse your lips and imagine that you are blowing up a balloon. As you exhale, let yourself relax and imagine your entire body going loose and limp. It should take you twice as long to exhale as it did to inhale.

In order to fully relax, do a sequence of 20 abdominal breaths. Try to keep your breathing smooth and regular throughout, without gulping air or exhaling suddenly. Try to do this breathing exercise both morning and evening.

If you're interested in learning meditation to control stress, I suggest contacting a local Yoga school.