There is a very interesting study Transcranial Direct Current Stimulation (tDCS) for Panic Disorder (I would assume the same result for Anxiety issues). – Source: Journal of Depression and Anxiety website.
The study discussions a woman that developed panic attacks and drugs did not help. What did work with tDCS Treatments.
“Ms. S.” developed panic attacks progressively more frequent during the past 3 years despite adequate treatment protocols with several medicines in adequate doses…” and the article goes on to list many anti-depressants / anti-anxiety meds she tried.
The image below shows the results of her Hamilton Anxiety Rating Scale (HARS) that dropped after the tDCS treatment (results were checked up to 30 days after).
The cathode (negative) was positioned over the right dorsolateral prefrontal cortex (DLPFC) F4 and the anode (postive) was placed extracephalic over the contralateral deltoid. We used a direct current of 2.0 mA for 30 minutes per day. The 25 cm2 rubber electrodes were wrapped in cotton material, which was moistened with saline as to reduce impedance. For assessment of anxiety symptoms we used the Hamilton Anxiety Rating Scale (HARS). We also assessed depressive symptoms through the Hamilton Depression Rating Scale (HDRS) – version 17 itens; and cognitive functions with the Montreal cognitive Assessment (MOCA).