BRAND NAMES
 MECHANISM OF ACTION
Desvenlafaxine, the major active metabolite of venlafaxine (Effexor), is a selective serotonin and norepinephrine reuptake inhibitor (SNRI). Higher affinity was found for the human serotonin transporter compared with the norepinephrine transporter. The assays indicate that desvenlafaxine is approximately 10-fold more potent at inhibiting serotonin uptake than norepinephrine uptake
Desvenlafaxine is used to treat major depression disorder. A major depressive episode implies a prominent and relatively persistent depressed or dysphoric mood that usually interferes with daily functioning (nearly every day for at least 2 weeks; it should include at least 4 of the following 8 symptoms: change in appetite, change in sleep, psychomotor agitation or retardation, loss of interest in usual activities or decrease in sexual drive, increased fatigue, feelings of guilt or worthlessness, slowed thinking or impaired concentration, and a suicide attempt or suicidal ideation
Major depression disorder:: The recommended dose is 50 mg/day once daily, with or without food. It is generally agreed that acute episodes of major depressive disorder require several months or longer of sustained pharmacologic therapy.
When discontinuing therapy, gradual dose reduction is recommended whenever possible to minimize discontinuation symptoms
- Hypersensitivity to Desvenlafaxine or to Venlafaxine
- It's use within 14 days of stopping an MAOI because of an increased risk of serotonin syndrome
- Do not start Desvenlafaxine in a patient who is being treated with linezolid or intravenous methylene blue (increased risk of serotonin syndrome)
 WARNINGS AND PRECAUTIONS
- FDA Black Box Warning for Desvenlafaxine: Antidepressants increased the risk compared to placebo of suicidal thinking and behavior (suicidality) in children, adolescents, and young adults in short-term studies of Major Depressive Disorder (MDD) and other psychiatric disorders. Anyone considering the use of Desvenlafaxine or any other antidepressant in a child, adolescent, or young adult must balance this risk with the clinical need. Short-term studies did not show an increase in the risk of suicidality with antidepressants compared to placebo in adults beyond age 24; there was a reduction in risk with antidepressants compared to placebo in adults aged 65 and older. Depression and certain other psychiatric disorders are themselves associated with increases in the risk of suicide. Patients of all ages who are started on antidepressant therapy should be monitored appropriately and observed closely for clinical worsening, suicidality, or unusual changes in behavior. Families and caregivers should be advised of the need for close observation and communication with the prescriber. Desvenlafaxine is not approved for use in pediatric patients.
- Serotonin Syndrome: Serotonin syndrome has been reported with SSRIs and SNRIs, including Desvenlafaxine, both when taken alone, but especially when co-administered with other serotonergic agents (including Triptans, Tricyclic antidepressants, Fentanyl, Lithium, Tramadol, Tryptophan, Buspirone and St. John’s Wort) and with drugs that impair metabolism of serotonin (in particular, MAOI, both those intended to treat psychiatric disorders and also others, such as Linezolid and intravenous Methylene blue). Serotonin syndrome symptoms may include mental status changes (e.g., agitation, hallucinations, coma), autonomic instability (e.g., tachycardia, labile blood pressure, hyperthermia), neuromuscular aberrations (e.g., hyperreflexia, incoordination) and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea).If such symptoms occur, discontinue Desvenlafaxine and initiate supportive treatment. If concomitant use of Desvenlafaxine with other serotonergic drugs is clinically warranted, patients should be made aware of a potential increased risk for serotonin syndrome, particularly during treatment initiation and dose increases.
- Abnormal Bleeding: May increase the risk of bleeding. Use with NSAIDs, Aspirin, Warfarin, or drugs that affect coagulation may potentiate the risk of gastrointestinal or other bleeding
- Hyponatremia: Hyponatremia has been reported with Desvenlafaxine use, either alone or in combination with some diuretics (Hydrochlorothiazide, Furosemide). Hyponatremia appears to be the result of the syndrome of inappropriate antidiuretic hormone secretion (SIADH). Signs and symptoms include headache, new or increased seizure frequency, difficulty concentrating, memory impairment, confusion, weakness, and unsteadiness, which can lead to fall. Severe Hyponatremia may cause hallucination, syncope, seizure, coma, respiratory arrest, and death.
- Monitor blood pressure especially in patients with high baseline blood pressure (increases in blood pressure were observed in clinical studies)
- Seizure: Can occur.Use with caution in patients with a history of seizures
- Avoid use of alcohol
- Caution when using heavy machinery
 PREGNANCY AND LACTATION
- Pregnancy Category C (US). Desvenlafaxine should be used during pregnancy only if the potential benefits justify the potential risks to the fetus.
- Nursing Mothers: Desvenlafaxine is excreted in human milk. Because of the potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
 SIDE EFFECTS
Most common adverse reactions were: Nausea, dizziness, insomnia, hyperhidrosis, constipation, somnolence, decreased appetite, anxiety, and specific male sexual function disorders (decreased libido, delayed ejaculation and erectile dysfunction)
There is an increased incidence of orthostatic hypotension in Desvenlafaxine treated patients ≥ 65 years.
 RELATED LINKS
|Tricyclic antidepressants||Amitriptyline (Elavil, Laroxyl) • Clomipramine (Anafranil) • Doxepin (Sinequan) • Imipramine (Tofranil) • Nortriptyline (Aventyl, Pamelor) • Trimipramine (Surmontil)|
|Selective serotonin reuptake inhibitors (SSRIs)||Citalopram (Celexa, Seropram) • Escitalopram (Cipralex, Lexapro) • Fluoxetine (Prozac) • Fluvoxamine (Luvox, Maveral) • Paroxetine (Paxil, Seroxat) • Sertraline (Zoloft)|
|Serotonin–norepinephrine reuptake inhibitors (SNRIs)||Desvenlafaxine (Pristiq) • Duloxetine (Cymbalta, Xeristar) • Venlafaxine (Efexor, Effexor)|
|Serotonin antagonists and reuptake inhibitors (SARIs)||Trazodone (Desyrel, Oleptro)|
|Norepinephrine reuptake inhibitors (NRIs)||Maprotiline (Ludiomil) • Reboxetine (Edronax)|
|Norepinephrine-dopamine reuptake inhibitors (NDRIs)||Bupropion (Wellbutrin)|
|Noradrenergic and specific serotonergic antidepressants (NaSSAs)||Mianserin (Lantanon) • Mirtazapine (Remeron)|
|Norepinephrine-dopamine disinhibitors (NDDIs)||Agomelatine (Valdoxan, Thymanax)|
|Monoamine oxidase inhibitors Nonselective||Tranylcypromine (Parnate)|
|Monoamine oxidase inhibitors B-Selective||Selegiline (Transdermal) (Emsam)|
|Others||5-Hydroxytryptophan • S-Adenosyl methionine • Hypericum (St John's wort)|