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- 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.
- 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.