This caused me to have terrible insomnia. I used the device twice the first day (as directed). I had a horrible headache and my mind was spinning the entire night in a way that I had never experienced before. The next day I used the device once around noon....for the next 3 nights I had the same awful headache and awful insomnia (despite stopping use of the device). I contacted fisher Wallace and they told me it wasnt because of the device, which is completely untrue. Ive never felt that way before. They advised I start on level 1...after a week of not using the device and finally returning to normal sleep, I tried the device again around noon on level one. Insomnia again that night. Its 100% from the device. I feel awful and Im not using that thing again. The company is not honest about the side effects it can cause.