Nurses Compass
Drug Guide
Desvenlafaxine
Classification
Therapeutic: Antidepressant
Pharmacological: Serotonin-Norepinephrine Reuptake Inhibitor (SNRI)
FDA Approved Indications
- Major Depressive Disorder
Mechanism of Action
Desvenlafaxine inhibits the reuptake of serotonin and norepinephrine in the central nervous system, increasing their levels in the synaptic cleft and helping to alleviate depression symptoms.
Dosage and Administration
Adult: Starting dose is 50 mg once daily, which may be increased to a maximum of 400 mg per day based on response and tolerability.
Pediatric: Not approved for use in pediatric patients.
Geriatric: Start at lower doses due to increased risk of side effects; monitor closely.
Renal Impairment: Dose adjustment may be necessary; refer to specific guidelines.
Hepatic Impairment: Use with caution; lower initial doses recommended.
Pharmacokinetics
Absorption: Well absorbed orally with approximately 80% bioavailability.
Distribution: Widely distributed; protein binding approximately 30%.
Metabolism: Primarily metabolized by conjugation (glucuronidation).
Excretion: Excreted mainly via urine; some in feces.
Half Life: Approximately 11 hours.
Contraindications
- Hypersensitivity to desvenlafaxine or venlafaxine.
- Use of monoamine oxidase inhibitors (MAOIs) within 14 days.
- History of medication-induced mania/hypomania.
Precautions
- History of hypertension or uncontrolled high blood pressure.
- Increased risk of suicidal thoughts particularly in young adults and adolescents.
- Serotonin syndrome risk with concomitant serotonergic drugs.
- Monitor blood pressure regularly.
Adverse Reactions - Common
- Nausea (Likely)
- Dizziness (Likely)
- Insomnia (Likely)
- Sweating (Likely)
- Dry mouth (Likely)
Adverse Reactions - Serious
- Serotonin syndrome (Rare)
- Hypertension (Less common)
- Hypertension with medication overdose (Rare)
- Changes in mood or behavior, including suicidal thoughts (Monitor closely during initial therapy or dose changes.)
Drug-Drug Interactions
- MAO inhibitors (risk of serotonin syndrome)
- Other serotonergic drugs (e.g., triptans, other antidepressants)
- Blood pressure medications (additive effects)
Drug-Food Interactions
N/ADrug-Herb Interactions
N/ANursing Implications
Assessment: Monitor mood, suicidal ideation, blood pressure, and adverse effects.
Diagnoses:
- Risk for injury related to dizziness or hypertension.
- Risk for suicide.
Implementation: Administer once daily; take with or without food. Educate patient about potential adverse effects. Regularly monitor blood pressure and mental status.
Evaluation: Assess mood improvement, monitor side effects, and verify blood pressure stability.
Patient/Family Teaching
- Do not abruptly stop medication.
- Report worsening mood, suicidal thoughts, or unusual side effects.
- Avoid alcohol and other CNS depressants.
- Be aware of signs of serotonin syndrome and hypertensive episodes.
Special Considerations
Black Box Warnings:
- Increased risk of suicidal thoughts in children, adolescents, and young adults.
- Serotonin syndrome risk.
Genetic Factors: Genetic variations may affect metabolism, but specific pharmacogenetic guidance is limited.
Lab Test Interference: None significant.
Overdose Management
Signs/Symptoms: Dizziness, somnolence, seizures, hypertension, serotonin syndrome symptoms.
Treatment: Supportive care, activated charcoal if ingestion was recent, manage blood pressure and seizures if they occur, serotonin syndrome management with supportive measures and specific therapies.
Storage and Handling
Storage: Store at room temperature, 20°C to 25°C (68°F to 77°F).
Stability: Stable in original container, away from light and moisture.