Firstly, don't get mislead that anxiety disorder is due to neurotransmitter imbalance. It is a learnt behaviour. It can be unlearned with the help of behaviour therapy. Many anxiety disorder patients initially needs some anxiolytic and antidepressants to get quick relief. But they need to change their thinking pattern.

Hi... Neuro-chemicals in our brain are responsible for transmitting information from one brain cell to another and this process is called Neurotransmission. Neuro-chemical imbalance can be restored using both Medication and Therapy. It depends what is causing this imbalance. In cases where the root cause is more genetic/biological, medication plays a bigger role. Whereas in cases where the cause is more psycho-social, therapy/counselling plays a major role in treatment. Please do not self diagnose and self treat yourself. Do consult a Psychiatrist and a Psychologist.