Three's company

Stimulants are the most effective drugs for ADHD, but the very things that make them effective - blocking norepinephrine and dopamine reuptake - can also lead to addiction and cause anxiety. Neurovance Inc.'s lead candidate for ADHD acts on two of the same neurotransmitters as stimulants, but adds serotonin, which could act as an abuse deterrent without sacrificing efficacy.

Low levels of dopamine and norepinephrine cause problems with cognition and focus. Stimulants inhibit transporter proteins responsible for clearing these neurotransmitters, thereby increasing their concentration in the prefrontal cortex. However, increased levels of norepinephrine also cause anxiety, and because higher levels of dopamine also trigger a reward/pleasure feeling, it can cause addiction. Non-stimulants do not have those liabilities, but the trade-off is a drop in efficacy. ...