A norepinephrine reuptake inhibitor (NRI or NERI) is a pharmaceutical drug that blocks the re-absorption of norepinephrine and epinephrine into the brain's cells. This prolongs the effect these neurotransmitters have on neural activity, stimulating improved mental acuity and alertness. The medication has a variety of uses, including the treatment of sleep disorders, major depressive disorder (MDD), and attention deficit hyperactivity disorder (ADHD). Side effects of NRIs include headaches, upset stomachs, and increased heart rates. Overdosing on the medication can lead to serious psychological and physiological problems, such as paranoia and acute brain damage.
The medication works by countering the action of the norepinephrine transporter, a mechanism that absorbs norepinephrene and epinephrine from the synapse back into the brain cells. This allows neurotransmitter receivers in the synapse to register the effects of the two neurotransmitters for much longer than normal. Norepinephrine and epinephrine, when being received, tell the brain to trigger the release of stored glucose for improved energy production, as well as increased heart rate. This increases blood and oxygen supply to the muscles and brain, which is then manifested as a surge in energy, motor function, and mental ability. This reaction categorizes a norepinephrine reuptake inhibitor as a stimulant drug.
Doctors often recommend NRIs for patients exhibiting symptoms associated with significantly decreased mental function. As a stimulant, the medication helps eliminate symptoms such as severe sluggishness, chronic and abnormal fatigue, and mental cloudiness. The stimulating effects also make it an option for the treatment of mood disorders associated with deficient neural activity. Psychiatrists believe that the medication can also benefit ADHD patients, with the resulting increased mental acuity allowing them to better focus on their activities.
Less conventional uses for norepinephrine reuptake inhibitor medication include the treatment of bed-wetting, sinus congestion, and overeating. The drug increases metabolic activity to a point where these issues are more easily handled by the patients. In addition, NRIs can be used in conjunction with a selective serotonin reuptake inhibitor (SSRI) to treat sexual dysfunction.
The side effects of norepinephrine reuptake inhibitor use arise from the over-stimulation of metabolic processes. Migraines, restlessness, and nausea can develop as a reaction to the medication. The drug's appetite-suppressing effects might also lead to the development of anorexia. When the drug is used beyond normal levels, the problems escalate; the patient's brain can suffer from severe toxicity, resulting in comas or death. Numerous experts support the use of norepinephrine reuptake inhibitors, however, saying that there is little to no risk of developing an addiction to the drugs.