I didn't ever have the nausea on strattera so I'm not sure. My guess is that with increased activity, it raises your blood pressure and that's what's causing the nausea. I did have some other side effects with strattera that lasted for months until they abided. Hang in there! In the meantime, stay hydrated, make sure you're eating healthy (balance your diet with lean proteins, fruits and veggies, and go easy on the sodium and processed foods with lots of sugar), and getting enough sleep. Those can all play a factor in overall feeling.