Dosing and uses of Viibryd (vilazodone)
Adult dosage forms and strengths
tablet
- 10mg
- 20mg
- 40mg
Major Depressive Disorder
10 mg PO qDay for 7 days with food; THEN increase to 20 mg qDay with food
May increase further up to 40 mg/day after a minimum of 7 days between dosage increases
Target maintenance dose: 20-40 mg/day
Dosing Modifications
Renal impairment (mild/moderate/severe): No dose adjustment recommended
Hepatic impairment (mild/moderate/severe): No dose adjustment recommended
CYP3A4 inhibitors
- Coadministration with strong CYP3A4 inhibitors (eg, ketoconazole): Not to exceed 20 mg PO qDay
- Coadministration with moderate CYP3A4 inhibitors (eg, erythromycin): Reduce dose to 20 mg/day if intolerable adverse events emerge
CYP3A4 inducers
- Coadministration with strong CYP3A4 inducers (eg, carbamazepine) for >14 days: Consider increasing vilazodone dose up to 2-fold (not to exceed 80 mg/day)
Dosing Considerations
Prior to initiating, screen patients for a personal or family history of bipolar disorder, mania, or hypomania
Pediatric dosage forms and strengths
Safety and efficacy not established
Viibryd (vilazodone) adverse (side) effects
>10%
Diarrhea (28%)
Nausea (23%)
1-10%
Dizziness (9%)
Xerostomia (8%)
Insomnia (6%)
Vomiting (5%)
Fatigue (4%)
Abnormal dreams (4%)
Libido decreased (4%)
Abnormal orgasm (3%)
Dyspepsia (3%)
Flatulence (3%)
Gastroenteritis (3%)
Somnolence (3%)
Paresthesia (3%)
Arthralgia (3%)
Restlessness/akathisia (3%)
Jittery sensation (2%)
Tremor (2%)
Delayed ejaculation (2%)
Erectile dysfunction (2%)
Increased appetite (2%)
Postmarketing Reports
General disorders and administrative site conditions: Irritability
Psychiatric disorders: Hallucinations, suicide attempt, suicidal ideation
Gastrointestinal disorders: Acute pancreatitis
Nervous system disorders: Sleep paralysis
Warnings
Black box warnings
Increased risk of suicidal thinking and behavior in children, adolescents, and young adults taking antidepressants for major depressive disorder and other psychiatric disorders
In children and young adults, the risks must be weighed against the benefits of taking antidepressants
Patients should be monitored closely for changes in behavior, clinical worsening, and suicidal tendencies; this should be done during the initial 1-2 months of therapy, as well as during dosage adjustments
The patient’s family should communicate any abrupt changes in behavior to the healthcare provider
Worsening behavior and suicidal tendencies that are not part of the presenting symptoms may require discontinuation of therapy
May worsen psychosis in some patients or cause a shift to mania or hypomania in bipolar disorder; patients should be screened for bipolar disorder prior to the initiation of therapy
Not approved for use in pediatric patients
Contraindications
Hypersensitivity
Coadministration with serotonergic drugs
- Do not use MAOIs concomitantly or within 14 days before initiating vilazodone or within 14 days after discontinuing vilazodone
- Symptoms include tremor, myoclonus, diaphoresis, nausea, vomiting, flushing, dizziness, hyperthermia with features resembling neuroleptic malignant syndrome, seizures, rigidity, autonomic instability with possible rapid fluctuations of vital signs, and mental status changes that include extreme agitation progressing to delirium and coma
- Starting vilazodone in a patient who is being treated with linezolid or IV methylene blue is contraindicated because of an increased risk of serotonin syndrome
- If linezolid or IV methylene blue must be administered, discontinue vilazodone immediately and monitor for CNS toxicity; may resume vilazodone 2 weeks after last linezolid or methylene blue dose
Cautions
May precipitate mixed/manic episode if initiated for bipolar disorder
May cause serotonin syndrome or neuroleptic malignant syndrome-like reactions, including agitation, hallucinations, coma, autonomic instability (eg, tachycardia, labile blood pressure, hyperthermia), neuromuscular aberrations (eg, hyperreflexia, incoordination), and/or gastrointestinal symptoms (eg, nausea, vomiting, diarrhea)
Use with caution in patients with history of seizures; has not been systematically evaluated in patients with seizure disorders (caution advised)
Serotonin reuptake inhibition may increase risk of bleeding (caution with drugs that inhibit platelets or coagulation)
Decrease dose gradually when discontinuing, to avoid dysphoric mood, irritability, insomnia, agitation, and confusion
CYP3A4 (major substrate); CYP2C19 (minor substrate, minor inhibitor, minor inducer); CYP2D6 (minor substrate, minor inhibitor); CYP2C8 (moderate inhibitor); increased plasma concentration (by 50%) observed when coadministered with strong CYP3A4 inhibitors (eg, ketoconazole)
Highly bound to plasma proteins (administration to patient taking another drug that is highly protein bound may increase free concentrations of the other drug)
Hyponatremia has been reported with other SSRIs, and SNRIs; common adverse effects include diarrhea, nausea, xerostomia, dizziness, and insomnia; can occur in association with syndrome of inappropriate antidiuretic hormone secretion (SIADH)
Bone fractures reported with antidepressant treatment; consider possibility of fragility fracture if antidepressant treated patient presents with unexplained bone pain, swelling, point tenderness, or bruising;
May cause sexual dysfunction
MAOIs (see Contraindications)
Coadministration with 5HT receptor agonist (ie, triptan), other serotonergic drugs (eg, SSRIs, SNRIs, buspirone, tramadol), or antidopaminergic drugs may increase risk for serotonin syndrome
Concomitant use with serotonin precursors (eg, tryptophan) not recommended
Serotonin reuptake inhibition may increase risk of bleeding (caution when coadministered with aspirin, NSAIDs, warfarin, and other anticoagulants)
Risk of mydriasis; may trigger angle closure attack in patients with angle closure glaucoma with anatomically narrow angles without a patent iridectomy
Pregnancy: Conflicting evidence regarding use of SSRIs during pregnancy and increased risk of persistent pulmonary hypertension of the newborn (PPHN; see Pregnancy)
Pregnancy and lactation
Pregnancy
Pregnancy category: C
Neonates exposed to serotonergic antidepressants late in the third trimester have developed complications requiring prolonged hospitalization, respiratory support, and tube feeding
Persistent pulmonary hypertension of the newborn
- Potential risk of PPHN when used during pregnancy
- Initial public health advisory in 2006 was based on a single published study; since then, there have been conflicting findings from new studies, making it unclear whether use of SSRIs during pregnancy can cause PPHN
- FDA has reviewed the additional new study results and has concluded that, given the conflicting results from different studies, it is premature to reach any conclusion about a possible link between SSRI use in pregnancy and PPHN
- FDA recommendation: FDA advises health-care professionals not to alter their current clinical practice of treating depression during pregnancy and to report any adverse events to the FDA MedWatch program
Lactation
Unknown whether distributed in human breast milk; is excreted into the milk of lactating rat; caution advised
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Viibryd (vilazodone)
Mechanism of action
Mechanism of antidepressant effect is not fully understood, but may be related to serotonergic activity in the CNS through selective inhibition of serotonin reuptake; no effect on norepinephrine or dopamine reuptake
Partial agonist of serotonergic 5-HT1A receptor whose activity may be altered in depression and anxiety
Absorption
Bioavailability: 72% (with food)
Peak plasma time: 4-5 hr
Peak plasma concentration: 156 ng/mL
AUC: 1645 ng•h/mL
Distribution
Protein bound: 96-99%
Metabolism
Extensively metabolized through CYP and non-CYP pathways (possibly by carboxylesterase); CYP3A4 is primarily responsible for its metabolism among CYP pathways, with minor contributions from CYP2C19 and CYP2D6
Elimination
Half-life: 25 hr
Excretion: Feces (2% unchanged), urine (1% unchanged)
Administration
Instructions
Take with food
Administration in fasted state (without food) may decrease blood concentration (AUC) by up to 50% and may result in decreased effectiveness
Discontinuing
Gradually reduce dose rather than discontinue abruptly
Taper from 40 mg/day to 20 mg/day for 4 days, followed by 10 mg/day7 for 3 days
Patients taking 20 mg/day should be tapered to 10 mg/day for 7 days
