Generic
Venlafaxine
8 brands available in the market
At a glance
Venlafaxine is a prescription medicine used in the treatment of depression and anxiety disorder. It alters the chemicals in the brain that cause symptoms of anxiety such as irritability, restlessness, lack of concentration, fatigue, sweating, increased heart rate and unwanted or racing thoughts.
Description
Venlafaxine and its active metabolite O-desmethylvenlafaxine selectively inhibit the neuronal reuptake of serotonin, norepinephrine and to a lesser extent dopamine. It has minimal affinity for muscarinic, histamine, or α1-adrenergic receptors.
Indications
- Depression
- Anxiety disorder
- Panic disorder
- Social anxiety disorder
- Generalized anxiety disorder
Therapeutic class
Serotonin-norepinephrine reuptake inhibitor (SNRI)
Pharmacological class
SNRI
Pharmacology
Venlafaxine and its active metabolite ODV are potent inhibitors of neuronal serotonin and norepinephrine reuptake and weak inhibitors of dopamine reuptake. Venlafaxine and ODV have no significant affinity for muscarinic, histaminergic, or α-1 adrenergic receptors.
Mechanism of action
Increases levels of serotonin and noradrenaline in the brain by inhibiting their reuptake.
Dosage
Adult Dose (Oral):
- Depression: Initially 75 mg/day in 2-3 divided doses; increase by up to 75 mg/day at intervals of 4 days or more; max 375 mg/day
- Extended-release: Initially 37.5-75 mg once daily; after 4-7 days may increase to 75 mg once daily; max 225 mg/day
- Panic disorder: Extended-release 37.5 mg once daily for 1 week; after 7 days increase to 75 mg once daily; max 225 mg/day
- Anxiety: Extended-release 37.5-75 mg once daily; max 225 mg/day
- Hepatic impairment: Mild to moderate: reduce dose by 50%
- Renal impairment: GFR <30 mL/min or hemodialysis: reduce dose by 50%
Administration
- Take with food
- Swallow whole; do not chew, crush or break
- Take at the same time each day
Missed dose
If you miss a dose, take it as soon as possible; if almost time for next dose, skip it; do not double the dose.
Side effects
Common Side Effects:
- Nausea
- Vomiting
- Dizziness
- Insomnia
- Decreased appetite
- Anxiety
- Constipation
- Increased sweating
- Sexual dysfunction
Precautions & warnings
- May affect ability to drive
- May take 2-4 weeks to start working
- Avoid alcohol; may cause excessive drowsiness and increase risk of liver damage
- Talk to doctor if sudden mood changes or suicidal thoughts occur
- Do not stop medication suddenly
Contraindications
- Uncontrolled hypertension
- High risk of serious ventricular arrhythmia
Drug interactions
- TCA, SSRI, SNRI, lithium, sibutramine, tramadol: increased risk of serotonin syndrome
- CYP3A4 inhibitors (ketoconazole, atazanavir, clarithromycin): may increase serum levels
- Haloperidol: may increase serum levels
- Indinavir: may decrease serum levels
- Aspirin, NSAIDs, warfarin and other anticoagulants: may increase bleeding risk
- MAOIs, linezolid, methylene blue: increased risk of serotonin syndrome (potentially fatal)
Food interactions
It is unsafe to consume alcohol with Venlafaxine.
Use in pregnancy
Use in Pregnancy: May be unsafe; animal studies show harmful effects; consult your doctor.
Pregnancy Category: C — always consult a doctor before taking during pregnancy.
Use in lactation
Use in Lactation: Probably unsafe; may pass into breast milk and harm the baby; consult your doctor.
Pediatric use
Pediatric dosage regimen established (ADHD: >40 kg: 12.5 mg/day initially; Depression: 37.5 mg/day initially)
Geriatric use
Caution required in elderly; dose adjustment may be needed
Renal / hepatic impairment
Renal Impairment: GFR <30 mL/min or hemodialysis: reduce dose by 50%
Hepatic Impairment: Mild to moderate: reduce dose by 50%
Overdose effects
Symptoms: Nausea, dizziness, tachycardia, serotonin syndrome.
Treatment: Supportive care.
Storage conditions
Store below 30°C in a dry place, protected from light; keep out of reach of children.