I have tried several products to improve focus and mental clarity. I have had a variety of responses. In some form, all of the different products did provide an increase in focus. However, some also increase anxiety, while others created a real let down effect, on the first day or two after I stopped their product. So far, with Qualia, I have not experienced any of the negative effects that I have experienced with other products. Qualia recommends the product be taken only 5 out of 7 day...Read more.