Norepinephrine-Dopamine Reuptake Inhibitors (NDRIs) are a class of antidepressant drugs. They are primarily used in the treatment of depression, but are also prescribed for smoking cessation and for the treatment of attention deficit disorder.
NDRIs work with the neurotransmitters norepinephrine and dopamine and therefore have a very different effect than selective serotonin reuptake inhibitors (SSRIs). Neurotransmitters are chemicals that act as messengers in the brain. It is important for these messengers to function properly. A mood disorder, such as an anxiety disorder or depression, can sometimes be explained by abnormalities in neurotransmitter activity. Research has suggested that abnormalities in the activity of certain neurotransmitters, including norepinephrine and dopamine, are associated with depression. Norepinephrine is a neurotransmitter that regulates alertness, concentration and motivation. Dopamine is often called the 'reward chemical' of the brain. It is involved in the regulation of mood and feelings of pleasure. SNRIs increase norepinephrine and dopamine levels in the brain by blocking the absorption of norepinephrine and dopamine into the cells that released them, in a process called "reuptake inhibition".
NDRIs are often not 'first line' antidepressants, but are instead used when other medications have been ineffective in relieving depression. Unlike most antidepressants, NDRIs are generally considered stimulants. Because they are stimulants, NDRIs have a unique set of side effects.
NDRI Side Effects Include:
Loss of appetite
Ringing in the ears
Shakiness and nervousness
Nausea and vomiting
In rare cases, NDRIs may increase suicidal thoughts. If a person who is taking an NDRI experiences thoughts of suicide, they should consult a doctor immediately.
The only NDRI that is approved by The Food and Drug Administration for the treatment of depression is Bupropion (Wellbutrin). Bupropion is offered in extended release (XL) form, which is taken once a day, and sustained-release (SR) which is taken twice. For the treatment of depression, it is often used in conjunction with an SSRI. It is one of the few antidepressants that do not have sexual side effects, and it is sometimes used to counteract the loss of libido and other sexual side effects caused by SSRIs. Bupropion has many uses besides the treatment of depression. The Food and Drug Administration approved it as a smoking cessation aid in 1997. Bupropion has also been used in the treatment of attention deficit disorder, seasonal affective disorder and obesity. According to a report by Drug Topics, Bupropion was the fourth most prescribed antidepressant of 2006.