It is not recommended to mix atomoxetine/concerta with cannabis as it can lead to potentially harmful interactions. Both medications can interact with THC and CBD in ways that may increase the concentration of the drugs in the blood, leading to more side effects such as headaches, nausea, vomiting, stomach pain, drowsiness, and dizziness. It is important to be cautious, especially with atomoxetine, when considering combining these medications with cannabis.