Schedule H

Oral

• Tablets: 5 mg, 10 mg (immediate-release)

Note: Sustained-release formulations are NOT AVAILABLE in India.

INDICATIONS + DOSING — FOR CLINICIAN USE ONLY

Primary Indications (Approved / Standard in India)

1. Generalised Anxiety Disorder (GAD)

For management of anxiety disorders or short-term relief of symptoms of anxiety with or without accompanying depression.

Parameter Recommendation

Starting dose 5 mg orally twice daily or 7.5 mg twice daily

Titration Increase by 5 mg/day every 2–3 days based on response and tolerability

Usual maintenance dose 15–30 mg/day in 2–3 divided doses

Maximum dose 60 mg/day (in divided doses)

Clinical Notes:

• Onset of anxiolytic action is delayed — typically 1–2 weeks; full effect may take 4–6 weeks

• Not effective for acute anxiety or panic attacks — do NOT prescribe PRN

• No significant sedation, cognitive impairment, or dependence potential compared to benzodiazepines

• Best suited for patients who cannot tolerate or have not responded to benzodiazepines

• Should be taken consistently at same times each day; may be taken with or without food

• Does not have cross-tolerance with benzodiazepines — patients switching from benzodiazepines should be tapered gradually

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

Indication Dose Duration Notes

Augmentation in Major Depressive Disorder (with SSRIs/SNRIs) 10–30 mg/day in divided doses ≥6 weeks trial added to antidepressant OFF-LABEL; Specialist only; Evidence: Small RCTs and Indian tertiary centre augmentation protocols

SSRI-Induced Sexual Dysfunction 5–15 mg/day in divided doses Ongoing with SSRI therapy OFF-LABEL; Specialist only; Evidence: Limited trials suggest modest benefit

Benzodiazepine Withdrawal Support 5–15 mg/day as adjunct during taper During taper period OFF-LABEL; Specialist only; Used in Indian de-addiction practice

PAEDIATRIC DOSING (Specialist Only)

Primary Indications (Approved / Standard in India)

NOT APPROVED for use in children and adolescents in India.

• Safety and efficacy not established in paediatric population for any indication

• Indian regulatory sources (CDSCO, NFI) do not list paediatric indications

Secondary Indications – Paediatrics (Off-label, if any)

Indication Age Dose Notes

Anxiety Disorders (Refractory to other treatments) ≥6 years Starting: 2.5–5 mg twice daily; Titration: Increase by 2.5–5 mg every 3–5 days; Maximum: 30 mg/day in divided doses OFF-LABEL; Specialist only (Child Psychiatry); Evidence: Limited; Based on international paediatric psychiatry protocols; Very limited Indian experience

Safety Monitoring in Paediatric Use:

• Behavioural changes, mood alterations

• Sedation, dizziness

• Gastrointestinal symptoms

• Efficacy assessment at 4–6 weeks

Not recommended below 6 years of age under any circumstances. Use above 6 years only under specialist paediatric psychiatry supervision.

• Known hypersensitivity to buspirone or any excipient

• Concurrent use with monoamine oxidase inhibitors (MAOIs) — risk of hypertensive crisis and serotonin syndrome

• Use within 14 days of discontinuing an MAOI

• Severe hepatic impairment

• Renal impairment — risk of drug accumulation; dose adjustment may be required

• Hepatic dysfunction — reduced clearance; avoid in severe impairment

• Concurrent use with serotonergic drugs (SSRIs, SNRIs, triptans, tramadol) — increased risk of serotonin syndrome

• Avoid concurrent alcohol and CNS depressants

• May impair alertness and motor coordination initially — caution with driving or operating machinery

• Not effective for panic disorder or acute situational anxiety

• Patients previously dependent on benzodiazepines may find buspirone less effective (no cross-tolerance; different mechanism)

• Diabetes mellitus — has been reported to interfere with diabetic control in some patients

Parameter Details

Risk Category Limited human data; animal studies do not show teratogenicity at therapeutic doses

Recommendation Avoid if possible; use only if potential benefit clearly outweighs risk

Preferred Alternatives SSRIs (sertraline preferred) for anxiety in pregnancy; psychological therapies as first-line

When May Be Used Only when SSRIs are contraindicated or not tolerated; requires specialist psychiatric and obstetric input

Monitoring Fetal growth surveillance; neonatal observation for sedation if used near term

Parameter Details

Compatibility Probably compatible; limited human data but expected low transfer

Drug Levels in Milk Unknown; likely low based on pharmacokinetic properties

Preferred Alternatives Sertraline (most data in lactation for anxiety/depression); psychological therapies

Infant Monitoring If breastfeeding continues, monitor infant for drowsiness, feeding difficulties, and adequate weight gain

Parameter Recommendation

Starting dose 5 mg once or twice daily (lower than adults)

Titration Slower titration — every 4–5 days; increase by 5 mg/day

Special Risks Increased sensitivity to CNS effects (dizziness, light-headedness); orthostatic hypotension; falls risk; age-related decline in hepatic and renal function may increase drug levels

Monitoring Blood pressure; fall risk assessment; cognitive function; adverse effects

Maximum dose Titrate cautiously; many elderly patients controlled at 15–30 mg/day

Note: Buspirone is generally better tolerated than benzodiazepines in elderly due to lack of sedation and cognitive impairment.

Interacting Drug Mechanism / Effect Recommendation

MAO Inhibitors (phenelzine, tranylcypromine, selegiline, moclobemide) Risk of hypertensive crisis and serotonin syndrome Contraindicated — do not use within 14 days of MAOI

Linezolid Weak MAOI activity; serotonin syndrome risk Avoid combination; if linezolid essential, discontinue buspirone

Methylene Blue (IV) MAOI activity; serotonin syndrome risk Avoid combination

Strong CYP3A4 inhibitors (ketoconazole, itraconazole, clarithromycin, ritonavir, nelfinavir) Markedly increased buspirone plasma levels Reduce buspirone dose; consider halving dose or avoiding combination

Grapefruit juice CYP3A4 inhibition in gut; increased buspirone levels Avoid concurrent consumption of large quantities

Strong CYP3A4 inducers (rifampicin, carbamazepine, phenytoin, phenobarbital) Reduced buspirone plasma levels and efficacy May need to increase buspirone dose; monitor for reduced efficacy

Interacting Drug Mechanism / Effect Recommendation

SSRIs (fluoxetine, sertraline, paroxetine, escitalopram) Additive serotonergic effect; potential serotonin syndrome risk Can be combined (often used for augmentation) but with caution; monitor for serotonin syndrome symptoms

SNRIs (venlafaxine, duloxetine) Additive serotonergic effect Use with caution; monitor for serotonin syndrome

Triptans (sumatriptan) Potential additive serotonergic effect Use with caution; monitor

Benzodiazepines May be co-prescribed during transition; no pharmacokinetic interaction Taper benzodiazepine gradually while establishing buspirone; monitor for sedation

Erythromycin Moderate CYP3A4 inhibitor; increased buspirone levels Monitor for increased adverse effects; consider dose reduction

Diltiazem / Verapamil Moderate CYP3A4 inhibitors; increased buspirone levels Monitor; may need dose adjustment

Antihypertensives Possible additive hypotensive effect Monitor blood pressure

Haloperidol Increased haloperidol levels reported Monitor for haloperidol adverse effects

Alcohol Additive CNS depression Advise avoidance

• Dizziness (most common)

• Headache

• Nausea

• Nervousness / Restlessness (early in treatment)

• Light-headedness

• Insomnia

• Drowsiness (less common than with benzodiazepines)

• Excitement / Agitation

• Dry mouth

• Fatigue

• Gastrointestinal upset (abdominal discomfort, diarrhoea)

Note: Adverse effects are generally mild and often improve with continued treatment.

Adverse Effect Clinical Action

Serotonin Syndrome (when combined with serotonergic drugs or MAOIs) — hyperthermia, rigidity, myoclonus, autonomic instability, altered mental status Discontinue immediately; supportive care; may require hospitalisation

Extrapyramidal Symptoms (rare) — dystonia, akathisia, parkinsonism Discontinue; supportive management; neurological evaluation

Movement Disorders (rare) Discontinue; evaluate

Allergic Reactions (rash, urticaria, angioedema) Discontinue; appropriate management

Chest Pain (rare; mechanism unclear) Evaluate for cardiac causes; consider discontinuation

1–2 weeks after initiation Assess tolerability, adverse effects (dizziness, nausea), early response

4–6 weeks Assess therapeutic response; if inadequate, consider dose adjustment or alternative

Long-term Periodic LFTs if continued beyond 2–3 months (especially in hepatic impairment); reassess continued need; monitor for serotonin syndrome if on concurrent serotonergic drugs

• Buspin (Sun Pharma)

• Buscalm (Intas)

• Anxipar (Torrent)

• Buspar (Various)

• Busirone (Various)

• Buspan (Mankind)

Note: All formulations are immediate-release tablets; no sustained-release formulations available in India. FDCs not applicable.

• Not included in NLEM; pricing not NPPA-controlled

• Prices vary across brands

• Generic versions available at lower cost

• Buspirone is NOT effective for acute anxiety relief — emphasise to patients that it must be taken regularly and effect takes 1–2 weeks to begin; do NOT prescribe on PRN basis

• Excellent choice for GAD in patients who cannot tolerate benzodiazepines or have substance use history — no sedation, cognitive impairment, or dependence potential

• No cross-tolerance with benzodiazepines — patients switching from long-term benzodiazepines may initially perceive buspirone as ineffective; gradual BZD taper with buspirone overlap is recommended

• Patient education is critical for adherence — clearly explain the delayed onset; many patients discontinue prematurely thinking it is not working

• Lower metabolic liability than benzodiazepines — safer in elderly and patients with respiratory compromise

• Useful as augmentation strategy in treatment-resistant depression when added to SSRIs — consider before more complex augmentation options

Buspirone; generalised anxiety disorder; GAD; anxiolytic; non-benzodiazepine; azapirone; 5-HT1A agonist; no dependence; delayed onset; renal-safe; elderly-friendly; Schedule H

RxIndia v1.0 — 04 Apr 2025

• CDSCO approved product information

• Indian Pharmacopoeia (IP)

• National Formulary of India (NFI)

• API Textbook of Medicine — Psychiatry chapter

• AIIMS Psychiatry Department Treatment Protocols

• Indian Psychiatric Society Practice Guidelines

• ICMR Guidelines on Mental Health

• Goodman & Gilman's: The Pharmacological Basis of Therapeutics

• Harrison's Principles of Internal Medicine

• International RCTs (for off-label indications — marked accordingly)