Schedule H

Oral

• Tablet 5 mg

• Tablet 10 mg

• Tablet 15 mg

• Tablet 20 mg

Note: Availability in Indian markets is limited; use remains specialist-driven.

INDICATIONS + DOSING — FOR CLINICIAN USE ONLY

Primary Indications (Approved / Standard in India)

Partial Seizures (Adjunct Therapy) — Adults and Adolescents ≥12 years

✅ Approved only as add-on therapy for refractory partial seizures not adequately controlled on standard AEDs.

⚠️ Initiation and dose adjustments should be under specialist supervision only.

Parameter Dosing Details

Starting dose 4 mg/day (single or divided dose)

Titration Increase by 4–8 mg at weekly intervals

Usual maintenance dose 16–56 mg/day in 2–4 divided doses

Maximum dose 56 mg/day

Key Clinical Notes:

• Patients on enzyme-inducing AEDs (phenytoin, carbamazepine, phenobarbital) may require higher doses

• Patients NOT on CYP inducers: use lower maintenance doses

• Avoid rapid titration — increases CNS adverse effects

• Not approved as monotherapy in India

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

Indication Dose Notes

Generalized Anxiety Disorder (OFF-LABEL) Starting: 4 mg at bedtime; Titrate over 3–4 weeks; Maximum: ≤24 mg/day Specialist only; Evidence: Limited RCTs internationally; Not part of standard Indian psychiatry protocols

Neuropathic Pain (e.g., post-herpetic neuralgia) (OFF-LABEL) 4–12 mg/day in divided doses Specialist only; Evidence: Modest benefit in small studies; Not first-line therapy

PAEDIATRIC DOSING (Specialist Only)

Primary Indications (Approved / Standard in India)

Partial Seizures (Adjunct) — Age 12–18 years

Parameter Dosing Details

Starting dose 4 mg/day (1–2 divided doses)

Titration Increase by 4–8 mg weekly

Usual maintenance dose 16–32 mg/day in divided doses

Maximum dose 0.5–1 mg/kg/day; not exceeding 56 mg/day

Safety Monitoring:

• Monitor for somnolence, behavioral changes, and paradoxical seizure worsening

• Use only under paediatric neurology supervision

⛔ Children <12 years: NOT RECOMMENDED due to insufficient safety and efficacy data. Use only under specialist supervision if ever considered.

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

Not applicable.

Mild to moderate impairment No dose adjustment required

Severe impairment / ESRD Limited data; use cautiously with close clinical monitoring

Hemodialysis No specific supplementation data available; use with caution

• Known hypersensitivity to tiagabine or any excipients

• Severe hepatic impairment

• Active suicidal ideation or recent suicide attempt (relative contraindication — requires careful specialist assessment)

• Concurrent use of CNS depressants (increased sedation and confusion risk)

• History of status epilepticus or seizure worsening on AED therapy

• Underlying hepatic dysfunction

• Avoid abrupt discontinuation — risk of rebound seizures

• Risk of non-convulsive status epilepticus, particularly in overdose or off-label misuse

• Depression or psychiatric comorbidities

Parameter Details

Risk category Not classified under Indian regulatory system; limited human data

Animal studies Some evidence of teratogenicity

Human data Inconclusive

Recommendation Use only if potential benefit justifies risk; specialist consultation mandatory

Preferred alternatives Carbamazepine, lamotrigine (depending on seizure type and clinical context)

Monitoring Fetal growth surveillance; maternal seizure control assessment

Parameter Details

Excretion in milk Likely excreted (specific data limited)

Compatibility Use with caution

Preferred alternatives Lamotrigine (if AED required during breastfeeding)

Infant monitoring Sedation, poor feeding, inadequate weight gain

Parameter Recommendation

Starting dose 2–4 mg/day

Titration Slower than adults; allow 2 weeks between dose increases

Extra risks Falls, confusion, excessive sedation

Other considerations Reduce dose if hepatic function impaired; monitor frequently

Interacting Drug/Class Effect Management

CYP3A4 inducers (carbamazepine, phenytoin, phenobarbital, rifampicin) Decreased tiagabine levels Higher tiagabine dose may be required

Valproate Slight inhibition of tiagabine clearance May require tiagabine dose reduction

Alcohol and sedatives Enhanced CNS depression Avoid combination or monitor closely

Interacting Drug/Class Effect Management

Oral contraceptives No significant interaction reported Monitor efficacy

SSRIs, antipsychotics Additive CNS effects (sedation, cognitive impairment) Use with caution; monitor

Other GABAergic AEDs (vigabatrin, benzodiazepines) Potential additive sedation and CNS effects Use with caution

• Dizziness

• Somnolence

• Fatigue

• Nervousness

• Tremor

• Difficulty concentrating

• Irritability

• Nausea

Most adverse effects are dose-related and may diminish with slower titration.

Adverse Effect Clinical Action

Status epilepticus (especially with off-label monotherapy use) Immediate discontinuation; emergency management

Non-convulsive status epilepticus Discontinue; specialist review

New-onset seizures in non-epileptic patients Discontinue; investigate

Psychosis, hallucinations Discontinue; psychiatric evaluation

Suicidal ideation Monitor closely, especially in adolescents; discontinue if severe

Phase Parameters

Baseline LFTs (if hepatic risk factors present); seizure type/frequency documentation; cognitive/psychiatric status

During titration Weekly: sedation, mood changes, seizure frequency

Long-term Periodic seizure assessment; mood/behavioral evaluation; LFTs if hepatotoxicity suspected

Blood levels Therapeutic drug monitoring not routinely required

• Gabitril (Sanofi)

• Tiagabin (Intas)

• TGB (Zydus)

Note: Market availability may fluctuate; confirm local availability before prescribing.

• Not included in NLEM

• Not under NPPA price control

1. Adjunct only — Tiagabine is approved solely as add-on therapy for partial seizures; never use as monotherapy.

1. Start low, go slow — Gradual titration minimizes CNS adverse effects (dizziness, somnolence).

1. Enzyme inducer interaction — Patients on carbamazepine/phenytoin require higher tiagabine doses; those not on inducers need lower doses.

1. Paradoxical seizures — Monitor for seizure worsening or new-onset seizures, especially in off-label settings.

1. Reserve for refractory cases — Not a first-line AED; use only under neurologist supervision for difficult-to-control partial epilepsy.

1. Avoid in non-epileptic patients — Risk of non-convulsive status epilepticus when used off-label in patients without epilepsy.

tiagabine; epilepsy; partial seizures; AED; GABA reuptake inhibitor; adjunctive therapy; neurology-specialist; non-NLEM; pregnancy-caution; refractory seizures

RxIndia v0.2 — 12 Jan 2025

• CDSCO approved package insert (Tiagabine)

• Indian Pharmacopoeia

• API Textbook of Medicine

• AIIMS Neurology Treatment Guidelines

• Product information from Indian pharmaceutical manufacturers

• Goodman & Gilman's The Pharmacological Basis of Therapeutics (pharmacokinetics and drug interactions)

• International RCTs (for off-label indications — clearly demarcated)