Strattera often takes several weeks to start working. Doctors may prescribe both medications when switching from a stimulant to Strattera, then taper off the stimulant as the Strattera begins to work. Taking the two together during an adjustment period is quite common and is safe. However, it is not the usual practice to use both a stimulant and Strattera over the long term. Two months should be enough time to see an effect. If it’s clear that Strattera is not working, it would be better to try something else instead of that medication, not in addition to it.