Duloxetine

Duloxetine is a selective serotonin and norepinephrine reuptake inhibitor (SNRI) antidepressants used for treating depression, anxiety disorder, and pain. Other drugs in this class include milnacipran(Savella), venlafaxine (Effexor), and desvenlafaxine (Pristiq). Duloxetine affects neurotransmitters, the chemicals that nerves within the brain make and release in order to communicate with one another. Neurotransmitters either travel across the space between nerves and attach to receptors on the surface of nearby nerves or they attach to receptors on the surface of the nerves that produced them, to be taken up by the nerve and released again (a process referred to as re-uptake).

Many experts believe that an imbalance among neurotransmitters is the cause of depression as well as other psychiatric disorders. Serotonin and norepinephrine are two neurotransmitters released by nerves in the brain. Duloxetine works by preventing the reuptake of serotonin and epinephrine by nerves after they have been released. Since uptake is an important mechanism for removing released neurotransmitters and terminating their actions on adjacent nerves, the reduced uptake caused by duloxetine increases the effect of serotonin and norepinephrine in the brain. The mechanism responsible for its effectiveness treating pain is not known but also is thought to involve its effects on serotonin and norepinephrine in the brain. Duloxetine was approved by the FDA in August 2004.

Duloxetine is used for the treatment of depression, generalized anxiety disorder, pain associated with diabetic peripheral neuropathy, fibromyalgia, and chronic musculoskeletal pain.

The most common side effects of duloxetine are nausea, dry mouth, constipation, diarrhea, fatigue, difficulty sleeping, and dizziness. Increased blood pressure can occur and should be monitored. Seizures have been reported. Sexual dysfunction (decreased sex drive and delayed orgasm and ejaculation) has been associated with duloxetine.

Some patients may experience withdrawal reactions upon stopping duloxetine. Symptoms of withdrawal include:

dizziness,

anxiety,

nausea,

vomiting,

nervousness,

diarrhea,

irritability, and

insomnia.

The dose of duloxetine should be gradually reduced when therapy is discontinued to prevent symptoms of withdrawal.

Antidepressants increased the risk of suicidal thinking and behavior (suicidality) in short-term studies in children and adolescents with depression and other psychiatric disorders. Anyone considering the use of duloxetine or any other antidepressant in a child or adolescent must balance this risk with the clinical need. Patients who are started on therapy should be closely observed for clinical worsening, suicidality, or unusual changes in behavior.