Therapeutic Action
Antiseizure (antiepileptic)
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Individual generic drug information
Extracted information for PHENYTOIN only.
Antiseizure (antiepileptic)
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Epilepsy: generalised tonic-clonic seizures and focal (partial) seizures
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Extracted information for PHENYTOIN only.
Administer with caution to patients with hepatic impairment (reduce dosage), heart failure, atrioventricular block, cardiac rhythm disorders, hypotension. May cause: drowsiness (caution when driving/operating machinery), dizziness, headache, behavioural disturbances, insomnia; gastrointestinal disturbances (nausea, vomiting), vitamin D deficiency (consider supplementation), osteoporosis, hepatotoxicity and gingival hypertrophy; rarely: haematologic disorders (thrombocytopenia, agranulocytosis, anaemia), hypersensitivity reactions (including severe cutaneous reactions such as Stevens-Johnson, Lyell and DRESS syndromes). In these cases, stop treatment. Early symptoms such as fever, rash, mouth ulcers and bleeding require immediate medical attention. If possible, perform at least FBC and liver enzymes, at baseline then regularly during treatment. Avoid or monitor the combination with: rifampicin, mefloquine (reduced effect of PHT); sulfonamides, chloramphenicol, fluconazole, isoniazid, fluoxetine, omeprazole (increased PHT toxicity); drugs containing alcohol, benzodiazepines, opioid analgesics, antipsychotics, first-generation antihistamines (hydroxyzine, promethazine), antidepressants, other antiseizure medications, etc. (increased sedation). PHT may reduce the effect of many drugs: diazepam, midazolam, digoxin, corticosteroids, antimicrobials, some antiretrovirals, itraconazole, warfarin, etc. Adjust dosage if necessary. implants and oral contraceptives: use injectable medroxyprogesterone or an intrauterine device. Avoid alcohol during treatment (increased risk of adverse effects). Pregnancy: avoid (risk of cardiac malformations) In case of pregnancy during treatment, prefer a safer drug (levetiracetam). If PHT is the only option, provide counselling about the risks to the child; use the lowest effective dose. Administer folic acid high dose (5 mg daily) during the first trimester. Start as soon as possible, including during the preconception period in case of planned pregnancy. PHT plasma concentrations may decrease during pregnancy. Monitor clinical response; increase dose if needed then resume the usual dose after delivery. Monitor the child for a few days (risk of accumulation and drowsiness or withdrawal symptoms). Breast-feeding: administer with caution (excreted in milk); reduce the dose if increased during pregnancy.
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Extracted information for PHENYTOIN only.
100 mg tablet
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Start with a low dose then increase gradually based on patient's response and tolerance. Child 1 month to 11 years: start with 1.5 to 2.5 mg/kg 2 times daily; increase the daily dose by increments of 5 mg/kg every 3 to 4 weeks, up to 2.5 to 5 mg/kg 2 times daily if necessary (max. 7.5 mg/kg 2 times daily or 300 mg daily). Child 12 years and over: start with 75 to 150 mg 2 times daily; increase the daily dose by increments of 25 mg every 3 to 4 weeks, up to 150 to 200 mg 2 times daily if necessary (max. 300 mg 2 times daily). Adult: start with 150 to 300 mg once daily or 75 to 150 mg 2 times daily; increase the daily dose by increments of 50 mg every 3 to 4 weeks, up to 200 to 400 mg once daily or 100 to 250 mg 2 times daily if necessary (max. 400 mg once daily or 300 mg 2 times daily).
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As long as required. Do not stop treatment abruptly, even if changing treatment to another antiseizure medication.
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Extracted information for PHENYTOIN only.
PHT is not recommended for myoclonic and absence seizures (risk of worsening symptoms). Also comes in 30 mg/5 ml oral solution.
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– Below 25 °C
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Filter the extracted dose blocks for this individual drug.
start with 1.5 to 2.5 mg/kg 2 times daily; increase the daily dose by increments of 5 mg/kg every 3 to 4 weeks, up to 2.5 to 5 mg/kg 2 times daily if necessary (max. 7.5 mg/kg 2 times daily or 300 mg daily).
Candidate age grouping · source page 254
start with 75 to 150 mg 2 times daily; increase the daily dose by increments of 25 mg every 3 to 4 weeks, up to 150 to 200 mg 2 times daily if necessary (max. 300 mg 2 times daily).
Candidate age grouping · source page 254