Schedule H

Oral

• Tablets: 50 mg, 150 mg

INDICATIONS + DOSING — FOR CLINICIAN USE ONLY

Primary Indications (Approved / Standard in India)

1. Intestinal Helminthiasis (Ascaris lumbricoides, Ancylostoma duodenale, Necator americanus)

Parameter Adults Children ≥2 years

Starting dose 150 mg single dose 2.5 mg/kg (maximum 150 mg) single dose

Titration Not applicable Not applicable

Usual maintenance dose Not applicable (single-dose therapy) Not applicable (single-dose therapy)

Maximum dose 150 mg per dose 150 mg per dose

Clinical Notes:

• Administer after meals to minimise gastrointestinal upset

• May repeat after 7 days if infestation persists (confirmed by stool examination)

• Stool microscopy recommended before repeat dosing

1. Frequently Relapsing Nephrotic Syndrome (FRNS) / Steroid-Dependent Nephrotic Syndrome (SDNS) — Relapse Prevention

Paediatric Nephrology Specialist Supervision Mandatory

Parameter Dosing Details

Starting dose 2.5 mg/kg orally on alternate days

Titration Not applicable

Usual maintenance dose 2.5 mg/kg on alternate days (maximum 150 mg/dose)

Maximum dose 150 mg per dose

Duration 6–12 months; reassess at 6 months for continuation

Clinical Notes:

• Used as steroid-sparing agent in children with FRNS/SDNS

• Monitor complete blood count every 4–6 weeks throughout therapy

• Discontinue immediately if absolute neutrophil count falls below 1500/mm³

• Educate caregivers about signs of infection (fever, sore throat, oral ulcers)

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

Indication Dose Duration Notes

Adjunctive therapy in colorectal cancer Historical: 150 mg/day for 3 days every 2 weeks with 5-FU Variable OFF-LABEL; NOT RECOMMENDED — Discontinued from oncology practice due to toxicity and lack of survival benefit. Not used in current Indian oncology protocols

Dermatological conditions (warts, vitiligo) Variable (no standardised regimen) Variable OFF-LABEL — Limited evidence; use has declined significantly. Specialist dermatology supervision only if considered

PAEDIATRIC DOSING (Specialist Only)

Primary Indications

1. Intestinal Helminthiasis

<2 years Not recommended — —

2–12 years 2.5 mg/kg Single dose 150 mg

12 years 150 mg (adult dose) Single dose 150 mg

Clinical Notes:

• Administer after meals

• Repeat dose after 7 days only if stool examination confirms persistent infestation

• Monitor for nausea, allergic rash, or cytopenias with repeated dosing

1. Frequently Relapsing / Steroid-Dependent Nephrotic Syndrome — Relapse Prevention

Under Paediatric Nephrology Supervision Only

Parameter Details

Starting dose 2.5 mg/kg orally on alternate days

Titration Not applicable

Usual maintenance dose 2.5 mg/kg on alternate days

Maximum dose 150 mg per dose

Duration 6–12 months (reassess at 6 months)

Minimum age Generally ≥2 years

Safety Monitoring:

• Baseline: CBC with differential, liver function tests

• During therapy: CBC every 4–6 weeks

• Discontinue if leukopenia (WBC <4000/mm³), neutropenia, or signs of vasculitis (purpura, arthralgia)

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

Indication Dose Notes

Dermatological uses (vitiligo, warts) No standardised paediatric dosing OFF-LABEL — Limited data in children; not routinely recommended. Specialist dermatology only

Age Restriction Statement:

Not recommended in children below 2 years of age except under specialist supervision with clear indication.

Severe impairment (eGFR <30) Use with caution; periodic CBC monitoring essential

End-stage renal disease / Dialysis Avoid repeated use unless clearly indicated; specialist guidance required

• Known hypersensitivity to levamisole or any excipient

• History of levamisole-induced agranulocytosis

• Severe hepatic impairment

• Severe renal dysfunction (for repeated/long-term use)

• Concurrent use with drugs known to cause agranulocytosis (e.g., clozapine)

• Pre-existing bone marrow suppression

• History of autoimmune disease or vasculitis

• Seizure disorders (rare CNS effects reported)

• Elderly patients (increased risk of myelosuppression)

• Prolonged or repeated use — requires haematologic monitoring

• Concomitant use with hepatotoxic or myelotoxic agents

• Patients on anticoagulant therapy

Parameter Summary

Risk category Not recommended during pregnancy (limited human data)

Preferred alternatives Albendazole (after first trimester) for helminthiasis

When to use Only if potential benefit clearly outweighs risk; avoid for immunomodulatory use

Monitoring If inadvertently used: monitor fetal growth; obstetric follow-up

Parameter Summary

Compatibility Avoid if possible; insufficient data on milk excretion

Preferred alternatives Albendazole preferred for helminthiasis in lactating mothers

Drug levels in milk Unknown

Monitor in infant Gastrointestinal symptoms, allergic reactions, feeding difficulties

• Starting dose: Same as adults (150 mg single dose for helminthiasis)

• Titration: Not applicable for single-dose use; slower approach if immunomodulatory use considered

• Extra risks:

• Increased susceptibility to myelosuppression

• Higher incidence of drug-induced vasculitis

• Monitor CBC more frequently if repeated dosing required

• Recommendation: Avoid prolonged use; prefer alternative anthelmintics (albendazole) where possible

Drug Interaction Recommendation

Clozapine Additive risk of agranulocytosis AVOID — Contraindicated combination

Methotrexate Increased risk of myelosuppression Use with extreme caution; frequent CBC monitoring

Phenytoin Levamisole inhibits phenytoin metabolism; increased phenytoin levels Monitor for phenytoin toxicity; may require dose reduction

Warfarin Enhanced anticoagulant effect Monitor INR closely; adjust warfarin dose as needed

Drug Interaction Recommendation

Corticosteroids Additive immunosuppression (in nephrotic syndrome) Monitor for infections; adjust steroid tapering accordingly

Isoniazid, Rifampicin Potential additive hepatotoxicity Monitor LFTs; avoid prolonged concurrent use

Carbamazepine Compounded risk of leukopenia Periodic CBC monitoring recommended

Alcohol May cause disulfiram-like reaction (rare) Advise avoidance during treatment

• Gastrointestinal: Nausea, vomiting, abdominal cramps, diarrhoea

• Dermatologic: Skin rash, pruritus

• Central nervous system: Dizziness, headache

• General: Fatigue, flu-like symptoms (particularly with prolonged use)

• Taste disturbance: Metallic taste (uncommon)

Adverse Effect Clinical Action

Agranulocytosis Discontinue immediately; hospitalisation may be required; supportive care

Drug-induced vasculitis Purpura, arthralgia, skin necrosis — Stop drug; specialist referral

Seizures Rare; discontinue and evaluate

Hepatotoxicity Monitor LFTs; discontinue if significant elevation

Stevens-Johnson Syndrome / TEN Very rare; Discontinue immediately; emergency management

Phase Parameters Frequency

Baseline CBC with differential, LFTs Before starting therapy

Short-term (single dose for helminthiasis) None routinely required —

Long-term (immunomodulatory use) CBC with differential Every 4–6 weeks

Long-term (immunomodulatory use) LFTs Every 2–3 months

Additional Monitoring:

• Educate caregivers to report fever, sore throat, oral ulcers, unusual bleeding, or rash immediately

• Clinical assessment for signs of vasculitis at each visit

• Decaris (Johnson & Johnson / Janssen)

• Levotraz (Intas Pharmaceuticals)

• Vermisol (Khandelwal Laboratories)

• Deworm-L (East West Pharma)

Note: Fixed-dose combinations with albendazole are available but single-agent formulations are preferred for clarity in dosing.

• NLEM Status: Not currently listed under National List of Essential Medicines

• Government Supply: Available in generic form through public health facilities

• Anthelmintic use has declined — Albendazole and mebendazole are preferred for most intestinal helminthiases due to broader spectrum and better tolerability

• Primary role in India: Steroid-sparing agent in paediatric nephrotic syndrome (FRNS/SDNS); cost-effective alternative to cyclophosphamide or mycophenolate

• Agranulocytosis risk: Typically occurs between 2–12 weeks of therapy; weekly CBC monitoring in first 3 months is prudent in immunomodulatory use

• Caregiver education is critical: Teach parents to recognise early signs of infection or bleeding

• Do not repeat anthelmintic dose empirically — Confirm persistent infestation by stool microscopy before re-treating

• Historical oncology use is obsolete — Do not prescribe for colorectal cancer; causes significant toxicity without survival benefit

levamisole; nephrotic syndrome; FRNS; SDNS; immunomodulator; anthelmintic; paediatric nephrology; agranulocytosis; myelosuppression; Schedule H; ascariasis

RxIndia v1.0 — 27 Apr 2025

• CDSCO approved prescribing information

• Indian Pharmacopoeia

• NFI 2021

• IAP Guidelines — Management of Nephrotic Syndrome in Children

• API Textbook of Medicine

• AIIMS Paediatric Nephrology Protocols

• Government of India — National Guidelines for Parasitic Infections

• ICMR Treatment Guidelines (Soil-transmitted helminthiases)