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    Prescription under medical supervision


    Therapeutic action

    • Anticonvulsant, sedative and hypnotic


    • Epilepsy: tonic-clonic (grand mal) and partial (focal) seizures

    Forms and strengths

    • 50 mg and 60 mg tablets


    Follow national protocol.
    For information:

    • Child: initial dose of 3 to 4 mg/kg once daily or 1.5 to 2 mg/kg 2 times daily, increase to 8 mg/kg daily if necessary
    • Adult: initial dose of 2 mg/kg once daily at bedtime (max. 100 mg daily), then, increase gradually if necessary, to the maximum dose of 3 mg/kg 2 times daily or 2 mg/kg 3 times daily 


    • According to clinical response

    Contra-indications, adverse effects, precautions

    • Do not administer in respiratory depression.
    • May cause: drowsiness, depression of the central nervous system.
    • Do not stop treatment abruptly.
    • Risk of increased sedation when combined with alcohol and drugs acting on the central nervous system such as diazepam, chlorphenamine, chlorpromazine, etc.
    • Phenobarbital reduces the effectiveness of implants and oral contraceptives: use an intrauterine device (copper or levonorgestrel) or a progestogen-only injectable (medroxyprogesterone).
    • Pregnancy: avoid
    • Breast-feeding: avoid


    • Phenobarbital is subject to international controls: follow national regulations.
    • Plasma-concentrations are stable after 2 to 3 weeks. Caution: risk of accumulation.
    • If necessary, phenytoin may be combined with phenobarbital.
    • Also comes in 15 mg to 100 mg tablets.


    – Below 25 °C