Schedule H

Oral

Tablets: 10 mg, 20 mg, 40 mg

INDICATIONS + DOSING — FOR CLINICIAN USE ONLY

Primary Indications (Approved / Standard in India)

▶ Major Depressive Disorder (MDD) – Adults

Step Dose Notes

Starting dose 10 mg once daily Must be taken with food (absorption reduced by ~50% if fasting)

Titration 20 mg once daily after 7 days, then 40 mg once daily after another 7 days Titrate based on response and tolerability

Usual maintenance dose 20–40 mg once daily Therapeutic response may begin within 1–2 weeks

Maximum dose 40 mg once daily Higher doses not supported by efficacy data; increased adverse effect risk

Key Clinical Notes:

• Dual mechanism (SSRI + 5-HT1A partial agonism) may offer faster onset than conventional SSRIs

• Gradual taper recommended at discontinuation to minimise withdrawal symptoms

• Food is mandatory with each dose for optimal bioavailability

Secondary Indications — Adults (Off-label, if any)

Indication Dose Duration Notes

Generalised Anxiety Disorder (GAD) — OFF-LABEL 10 mg/day initially, titrate to 20–40 mg/day 4–12 weeks based on response Specialist only; supportive evidence from international RCTs; not standard Indian practice

PAEDIATRIC DOSING (Specialist Only)

Primary Indications (Approved / Standard in India)

Not applicable.

Vilazodone is NOT approved for use in children or adolescents under 18 years in India.

• Safety and efficacy have not been established in this population

• Increased risk of suicidal ideation in young patients treated with antidepressants

Secondary Indications — Paediatric Doses (Off-label, if any)

Not applicable.

Use only under exceptional circumstances with specialist psychiatrist supervision (e.g., research settings).

Mild to moderate impairment No dose adjustment required

• Concomitant use with MAO inhibitors, or within 14 days of stopping an MAOI

• Hypersensitivity to vilazodone or any excipient

• Concomitant use with linezolid

• Concomitant use with intravenous methylene blue

• Seizure disorder — may lower seizure threshold

• Risk of hyponatraemia — particularly in elderly or volume-depleted patients

• Bleeding tendency — caution with concurrent NSAIDs, antiplatelet agents, or anticoagulants

• Serotonin syndrome risk — especially with other serotonergic agents

• Bipolar disorder — may precipitate manic or hypomanic episodes; screen before initiating

• Angle-closure glaucoma predisposition — mydriasis may trigger acute episode

• Suicidal ideation — monitor closely, especially during first weeks of therapy or dose changes

Parameter Detail

Safety Caution advised — limited human data; animal studies suggest potential risk

Use in pregnancy Only if potential benefit clearly outweighs risk; preferably avoid in first trimester

Preferred alternatives Sertraline, fluoxetine (more established safety profiles in Indian obstetric practice)

Monitoring If used in third trimester: observe neonate for discontinuation symptoms, respiratory distress, feeding difficulties

Parameter Detail

Compatibility Not recommended — insufficient data on excretion into human milk

Milk levels Unknown; assumed low to moderate based on SSRI class behaviour

Preferred alternatives Sertraline or paroxetine (more established lactation safety data)

Infant monitoring If used: monitor for sedation, feeding difficulties, weight gain, irritability

• Starting dose: 10 mg once daily

• Titration: Slower titration recommended; increase dose at 2-week intervals if tolerated

• Special considerations:

• Increased risk of hyponatraemia (monitor serum sodium)

• Higher susceptibility to falls and dizziness

• Monitor for cognitive changes and excessive sedation

• Consider lower maximum target dose (20 mg/day) if tolerability is limited

Interacting Drug Effect/Risk Recommendation

MAO inhibitors (e.g., phenelzine, tranylcypromine) Severe serotonin syndrome risk Contraindicated; 14-day washout required before or after vilazodone

Linezolid Serotonergic interaction Contraindicated

IV Methylene blue Serotonergic interaction Contraindicated

Strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, ritonavir) Increased vilazodone plasma levels Reduce vilazodone dose to 20 mg/day maximum

Strong CYP3A4 inducers (e.g., rifampicin, carbamazepine, phenytoin) Reduced vilazodone efficacy Avoid combination; consider alternative antidepressant

Interacting Drug Effect/Risk Recommendation

Other SSRIs/SNRIs (e.g., fluoxetine, venlafaxine) Additive serotonergic effects Monitor for serotonin syndrome; avoid concurrent use if possible

Tramadol, pethidine Increased serotonin syndrome risk Use cautiously; monitor closely

Triptans (e.g., sumatriptan) Additive serotonergic effects Monitor for serotonin syndrome

NSAIDs, aspirin Increased bleeding risk Use cautiously, especially in elderly; consider gastroprotection

Anticoagulants (e.g., warfarin) Enhanced bleeding risk Monitor INR; watch for bleeding signs

Antiplatelet agents (e.g., clopidogrel) Increased bleeding risk Clinical monitoring advised

Alcohol Potentiates CNS effects Advise patients to avoid or limit alcohol

Antiepileptics May affect seizure control Monitor seizure frequency

• Diarrhoea (most frequent; often dose-limiting)

• Nausea

• Headache

• Dizziness

• Insomnia or somnolence

• Dry mouth

• Sexual dysfunction (may be lower than other SSRIs)

• Vomiting

Most adverse effects peak in first 1–2 weeks and may diminish with continued use.

Adverse Effect Clinical Note

Serotonin syndrome Discontinue immediately; provide supportive care; potentially life-threatening

Seizures Rare; discontinue drug and manage supportively

Suicidal ideation/behaviour Particularly in early treatment or young adults; requires close monitoring

Severe hyponatraemia May present as confusion, falls, seizures; check sodium levels

Activation of mania/hypomania Screen for bipolar disorder; discontinue if switching occurs

Abnormal bleeding GI bleeds, ecchymoses; risk increased with anticoagulants/NSAIDs

After initiation/dose change (first 2–4 weeks) Monitor for suicidal ideation, serotonin syndrome symptoms, emergence of mania, tolerability

Long-term Periodic mental status evaluation; weight monitoring; serum sodium in elderly; assess for sexual dysfunction; evaluate need for continued therapy

• Viladoz

• Vilazep

• Vilazo

• Vilahope

(Available as monotherapy tablets; no approved fixed-dose combinations in India)

Strength Approximate Price per Tablet

10 mg ₹8–15

20 mg ₹12–20

40 mg ₹18–30

• Not included in NLEM

• Prices vary across brands and retail outlets

• Not available through government supply programmes

1. Food is essential: Vilazodone must be taken with food — fasting reduces bioavailability by approximately 50%, leading to subtherapeutic levels.

1. Faster onset possible: The 5-HT1A partial agonist activity may contribute to earlier symptom relief compared to conventional SSRIs in some patients.

1. Sexual side effects: Some evidence suggests lower rates of sexual dysfunction compared to traditional SSRIs — consider for patients who have discontinued other SSRIs due to this adverse effect.

1. Diarrhoea management: GI side effects are common initially; taking with food and starting at 10 mg helps minimise this. Usually self-limiting within 1–2 weeks.

1. Taper on discontinuation: Do not stop abruptly — gradual dose reduction over weeks is necessary to prevent discontinuation syndrome.

1. Not first-line in elderly or hepatic impairment: Limited data in these populations; prefer established alternatives unless specific indication exists.

vilazodone; depression; MDD; SSRI; 5HT1A agonist; psychiatry; serotonin-syndrome-risk; hepatic-caution; take-with-food

RxIndia v1.0 — 29 May 2025

• CDSCO approved product information

• Indian product labels (Sun Pharma, Intas)

• NFI 2021

• API Textbook of Medicine (2022 edition)

• ICMR Guidelines — Depression Management

• Indian Psychiatric Society consensus recommendations

• Goodman & Gilman's Pharmacological Basis of Therapeutics

• International RCTs (for off-label GAD use — noted as off-label)