Hi- I'm experiencing various periods of weakness and dizziness, sudden fatigue and dry mouth. I drink plenty of fluids throughout the day, urinate normally, more frequently with caffeine, like normal- good blood pressure and resting heart rate (BP: 113/69 HR: 73 BPM). No other symptoms except nausea throughout most of the day. These dizzy spells come sporadically and without warning.. they tend to ease with some rest, but the spells have been lasting longer and happening more frequently. They aren't accompanied by headaches, just extreme nausea.