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Other brands with the same active ingredient
These brands contain the same active ingredient (Primidone). Same strength and form. Confirm the switch with your doctor or pharmacist.
Indications & Uses
Primidone 50 mg is indicated for:
Dosage Reference
Reference Information Only
Dosages shown are general references from official sources. Always consult your doctor or pharmacist for personalized dosing.
Adults:
Patients 8 years of age and older who have received no previous treatment may be started on primidone tablets according to the following regimen: Days 1 to 3: 100 to 125 mg at bedtime. Days 4 to 6: 100 to 125 mg. twice a day. Days 7 to 9: 100 to 125 mg three times a day. Day 10 to maintenance: 250 mg three times a day. For most adults and children 8 years of age and over, the usual maintenance dosage is three to four 250 mg primidone tablets in divided doses (250 mg three times a day or four times a day). If required, an increase to five or six 250 mg tablets daily may be made, but daily doses should not exceed 500 mg four times a day.Dosage should be individualized to provide maximum benefit. In some cases, serum blood level determinations of primidone may be necessary for optimal dosage adjustment. The clinically effective serum level for primidone is between 5 to 12 mcg/mL.
Side Effects
The most frequently occurring early side effects are ataxia and vertigo. These tend to disappear with continued therapy, or with reduction of initial dosage. Occasionally, the following have been reported: nausea, anorexia, vomiting, fatigue, hyperirritability, emotional disturbances, sexual impotency, diplopia, nystagmus, drowsiness, and morbilliform skin eruptions. Granulocytopenia, agranulocytosis, and red-cell hypoplasia and aplasia, have been reported rarely. These and, occasionally, other persistent or severe side effects may necessitate withdrawal of the drug. Megaloblastic anemia may occur as a rare idiosyncrasy to Rimidon and to other anticonvulsants. The anemia responds to folic acid without necessity of discontinuing medication.
Cautions & Contraindications
Warnings & Precautions
The total daily dosage should not exceed 2 g. Since Rimidon therapy generally extends over prolonged periods, a complete blood count and a sequential multiple analysis-12 (SMA-12) test should be made every 6 months.