Strattera (atomoxetine) is an oral medication used primarily to treat the symptoms of Attention Deficit Hyperactivity Disorder (ADHD) along with behavioral therapies and counseling. It is part of a class of medications called selective norepinephrine reuptake inhibitors (NRI).

It works by increasing the levels of norepinephrine in the brain, a chemical that plays an important role in maintaining mental acuity.

It is believed that a possible cause of attention deficit hyperactivity disorder (ADHD) is a low amount of the neurotransmitter norepinephrine. In the brain, the space between where two neurons meet to communicate is called a synapse, and the synapse is where norepinephrine and other neurotransmitters are used to communicate between neurons. In ADHD, people may not have enough norepinephrine in their brain. Normally after a chemical message is sent between neurons, the neurotransmitters are reabsorbed by the sending neuron (presynaptic neuron). A selective norepinephrine reuptake inhibitor will bind to the presynaptic neuron and prevent it from absorbing the norepinephrine, and leave the neurotransmitter active in the synapse, improving concentration, focus, and attention.