📋 Indications & Clinical Dosage
*All forms of epilepsy except typical absence seizures:*
ORAL: Adult: 60-180 mg once daily at night
Children 1 month-11 yrs: Initially 1-1.5 mg/kg twice daily, then increased in steps of 2 mg/kg daily as required; maintenance 2.5-4 mg/kg 1-2 times a day; 12-17 yrs: 60-180 mg once daily.
*Status epilepticus:*
BY IV INJ: Adult: 10 mg/kg (max. per dose 1 g), dose to be administered at a rate not more than 100 mg/minute, injection to be diluted 1 in 10 with water for injections
BY SLOW IV INJ: Children 1 month-11 yrs: Initially 20 mg/kg, dose to be administered at a rate no faster than 1 mg/kg/minute, then 2.5-5 mg/kg 1-2 times a day; 12-17 yrs: Initially 20 mg/kg (max. per dose 1 g), dose to be administered at a rate no faster than 1 mg/kg/minute, then 300 mg twice daily.
💊 Mode of Administration
Avoid rapid IV administration >50 mg/min; Avoid intra-arterial injection.
⛔ Contraindications
Severe respiratory depression.
⚠️ Precautions & Warnings
Avoid in acute porphyrias, children, debilitated, elderly, history of alcohol abuse, history of drug abuse, respiratory depression (avoid if severe). Consider vitamin D supplementation in patients who are immobilised for long periods or who have inadequate sun exposure or dietary intake of calcium. Renal and hepatic impairment, pulmonary insufficiency (contraindicated if severe). Withdraw gradually.
🔄 Drug Interactions
Coumarin anticoagulants, alcohol and other CMS depressants, oral contraceptives, griseofulvin, ri-fampicin, phenytoin, metronidazole, doxycycline, chloramphenicol, telithromycin, antidepressants, St. Johns Wort, antipsychotics, nucleoside reverse transcriptase inhibitors, protease inhibitors, eplerenone.
⚠️ Adverse Reactions / Side Effects
Agranulocytosis, ataxia, behavioural disturbances, cholestasis, depression, drowsiness, hallucinations, hepatitis, hyperkinesia, hyperactivity particularly in the elderly and in children, hypotension, impaired cognition and memory, irritability, lethargy, megaloblastic anaemia, nystagmus, osteomalacia, paradoxical excitement, respiratory depression, skin allergic reactions, thrombocytopenia. Rare: Antiepileptic Hypersensitivity Syndrome, Stevens-Johnson syndrome, suicidal ideation, toxic epidermal necrolysis
🤰 Pregnancy & Lactation Safety
Pregnancy Risk:
Contraindicated
Lactation / Breastfeeding:
Contraindicated
📚 Official Regulatory & Clinical References
- Drug Regulatory Authority of Pakistan (DRAP): Drug Registration, S.R.O. Price Gazettes & National Essential Medicines List (NEML).
- World Health Organization (WHO): Collaborating Centre for Drug Statistics Methodology (ATC/DDD Index).
- Formulary Standards: British National Formulary (BNF) & Pakistan National Formulary (PNF) guidelines.