Primidone

Methylphenidate may inhibit the metabolism of primidone. Downward dose adjustments may be required and plasma drug concentration should be monitored.

Enzyme-inducing drug that can double valproate clearance. Increased monitoring of valproate and primidone concentrations and dosage adjustment indicated.

Can double the clearance of valproate, resulting in lower valproate concentrations and potential loss of therapeutic effect.

Primidone administration causes folate deficiency through increased loss or metabolic interference.

Enzyme-inducing anti-epileptic drug that decreases imatinib AUC by 73%, significantly reducing imatinib exposure.

Primidone decreases lamotrigine concentrations by approximately 40%, requiring dose adjustment.

Increases metabolism of contraceptive steroids, reducing contraceptive effectiveness and potentially resulting in unintended pregnancy or unscheduled bleeding.

Acetazolamide decreases gastrointestinal absorption of primidone, reducing serum concentrations and potentially decreasing anticonvulsant effect.

Acetazolamide decreases gastrointestinal absorption of primidone, reducing serum concentrations and possibly decreasing anticonvulsant effect. Caution advised when beginning, discontinuing, or changing acetazolamide dose.

Acetazolamide decreases gastrointestinal absorption of primidone, potentially decreasing serum concentrations and anticonvulsant effect.

CYP3A4 inducer that decreases carbamazepine plasma levels. Carbamazepine levels and/or dosage adjustment may be necessary.

Can double the clearance of valproate, potentially decreasing valproate concentrations. Monitor valproate levels when introduced or withdrawn.

Higher dosage of eslicarbazepine acetate may be necessary. Primidone can induce enzymes that metabolize eslicarbazepine acetate and cause decreased plasma concentrations.

CYP3A4 inducer that decreases ganaxolone exposure and efficacy; ZTALMY dosage may need to be increased but should not exceed maximum daily dosage.

CYP3A4 inducer may decrease serum hydrocortisone concentrations and increase risk of adrenal crisis; may require dose increase.

Decreased lamotrigine concentration approximately 40%.

Decreases lamotrigine concentration approximately 40%.

Folic acid in large amounts may counteract the antiepileptic effect and increase seizure frequency in susceptible children.

Folic acid in large amounts may counteract antiepileptic effect and increase seizure frequency in susceptible children. Monitor patients taking levoleucovorin with this drug.

Folic acid in large amounts may counteract the antiepileptic effect and increase seizure frequency in susceptible children. Unclear if folinic acid has same effects, but they share metabolic pathways. Monitor patients.

Folic acid in large amounts may counteract antiepileptic effect and increase seizure frequency. Monitor patients taking folinic acid with antiepileptic drugs.

Methylphenidate may inhibit metabolism of this anticonvulsant. Downward dose adjustments may be required.

Methylphenidate may inhibit metabolism of primidone; downward dose adjustment may be required and plasma concentrations should be monitored.

Impairs folate absorption and increases metabolism of circulating folate.

Primidone decreases rufinamide concentration by 25-46%.

Primidone increases tiagabine clearance by 60%, which may require dose adjustments to maintain therapeutic efficacy.

Primidone is an enzyme-inducing drug that can increase valproate clearance and may double it. Monitoring of valproate and primidone concentrations and dosage adjustment are indicated.

Enzyme-inducing drug that can increase valproate clearance and double clearance rate. Increased monitoring of valproate and concomitant drug concentrations and dosage adjustment indicated.

Levetiracetam does not influence primidone plasma concentration and primidone does not influence levetiracetam pharmacokinetics.

Potential interaction with topiramate as a standard antiepileptic drug; specific effect not evaluated.