Nicotine is one of the active substances in tobacco and cigarettes. It is a very powerful stimulant that affects neural pathways that controls reward and pleasure which makes it a very addictive chemical. Thyroid hormone is also a stimulant. Thus, both nicotine and thyroid hormone together can cause very similar effects on the brain, heart, lungs, and intestines. Most people with hyperthyroidism have significant anxiety. The anxiety that you are feeling when smoking is related to the synergistic pyschostimulant effects of nicotine and thyroid hormone on the brain, heart, lungs, and intestines. I would recommend: -complete cessation of all nicotine contain products -Regular exercise, acupuncture, yoga, tai chi, and aromatherapy are associated with decreased anxiety -limit caffeine intake. -Alcohol can potentiate anxiety -pyschoeducation can be extremely helpful in regards to normal versus pathologic anxiety, the fight or flight response, and the physiology of anxiety