No serious drug interactions have been reported with concomitant use of - atomoxetine and clonidine - atomoxetine and propranolol. However, clonidine may enhance the effects of propranolol when taken together including AV blockade and sinus node dysfunction (both are not good).
Yes, Clonidine can help with anxiety, ADHD (inattention), drug withdrawals (alcohol, opioids), etc.
Next Steps
Always consult psychiatrist when in doubt