Started using Evekeo 10 mg 2 x daily. It is ineffective. Supposed to last 4-6 hours -- ACTUALLY 2 hours for me. After two hours I feel like one who is having a panic attack, tight chest, lump in throat ... I am a gastric bypass patient and have used Vyvanse 70 mg which is very effective for between four and five hours. Gastric Bypass patients find that extended release medications anathema because of malabsorption, lack of bioavailability that is a concrete result that the procedure restricts or removes the digestive system's integrity -- (Removal of the stomach's duodenum which produces the necessary acids, enzymes and proteins is truncated/restricted "absent" thereby er/xr formulas' CANNOT BE RELEASED appropriately) so that duration of extended release mechanism is...