Primidone

204 interactions 13 explained in plain English
Also sold as: Mysoline
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Jul 4, 2026 · Editorial policy · Data sources

Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →

Major

Primidone Edoxaban Savaysa Reduced edoxaban exposure and increased risk of thrombotic events Details Primidone Elacestrant Orserdu Reduced elacestrant exposure and reduced efficacy of elacestrant Details Primidone Encorafenib Braftovi Reduced encorafenib exposure and reduced efficacy of encorafenib Details Primidone Entrectinib Rozlytrek An increased risk of QT interval prolongation, reduced entrectinib exposure and reduced efficacy of entrectinib Details Primidone Eravacycline Injection Xerava Reduced CYP3A substrate exposure and reduced efficacy of CYP3A substrate Details Primidone Erdafitinib Balversa Reduced erdafitinib exposure Details Primidone Eribulin Injection Halaven An increased risk of QT interval prolongation Details Primidone Esketamine Nasal Spray Spravato Increased risk of sedation Details Primidone Esomeprazole Nexium Reduced esomeprazole exposure, reduced efficacy of esomeprazole, increased PHENobarbital exposure and an increased risk of PHENoba... Details Primidone Esomeprazole Injection Nexium Reduced esomeprazole exposure, reduced efficacy of esomeprazole, increased PHENobarbital exposure and an increased risk of PHENoba... Details Primidone Estradiol Delestrogen Reduced hormonal contraceptive exposure, reduced efficacy of hormonal contraceptive and an increased risk of breakthrough bleeding... Details Primidone Estradiol Topical Divigel Reduced hormonal contraceptive exposure, reduced efficacy of hormonal contraceptive and an increased risk of breakthrough bleeding... Details Primidone Estradiol Transdermal Patch Alora® Reduced hormonal contraceptive exposure, reduced efficacy of hormonal contraceptive and an increased risk of breakthrough bleeding... Details Primidone Everolimus Afinitor Reduced CYP3A substrate exposure and reduced efficacy of CYP3A substrate Details Primidone Exemestane Aromasin Reduced exemestane exposure Details Primidone Famotidine Calmicid An increased risk of QT interval prolongation Details Primidone Famotidine Injection Calmicid An increased risk of QT interval prolongation Details Primidone Felbamate Felbatol An increased risk of QT interval prolongation and an increased PHENobarbital exposure Details Primidone Felodipine Plendil® Reduced felodipine exposure and reduced efficacy of felodipine Details Primidone Fentanyl Transdermal Patch Duragesic® Increased risk of CNS depression and reduced exposure of fentaNYL Details Primidone Finerenone Kerendia Reduced finerenone exposure and reduced efficacy of finerenone Details Primidone Flecainide Tambocor® An increased risk of QT interval prolongation Details Primidone Fluvastatin Lescol Reduced CYP2C9 substrate exposure and reduced efficacy of CYP2C9 substrate Details Primidone Foscarnet Injection Foscavir An increased risk of QT interval prolongation Details Primidone Fostamatinib Tavalisse Reduced CYP3A substrate exposure and reduced efficacy of CYP3A substrate Details Primidone Fostemsavir Rukobia Reduced CYP3A substrate exposure and reduced efficacy of CYP3A substrate Details Primidone Galantamine Razadyne An increased risk of QT interval prolongation Details Primidone Gatifloxacin Ophthalmic Zymar® An increased risk of QT interval prolongation Details Primidone Gemifloxacin Factive An increased risk of QT interval prolongation Details Primidone Gilteritinib Xospata Reduced CYP3A substrate exposure and reduced efficacy of CYP3A substrate Details Primidone Glasdegib Daurismo An increased risk of QT interval prolongation, reduced glasdegib exposure and reduced efficacy of glasdegib Details Primidone Glimepiride Amaryl Reduced CYP2C9 substrate exposure and reduced efficacy of CYP2C9 substrate Details Primidone Goserelin Implant Zoladex An increased risk of QT interval prolongation Details Primidone Granisetron Transdermal Patch Sancuso An increased risk of QT interval prolongation and reduced granisetron exposure Details Primidone Granisetron Injection Granisol An increased risk of QT interval prolongation and reduced granisetron exposure Details Primidone Histrelin Implant Supprelin An increased risk of QT interval prolongation Details Primidone Hydrocortisone Ala-Cort Reduced hydrocortisone exposure and reduced efficacy of hydrocortisone Details Primidone Hydrocortisone Injection A-Hydrocort® Reduced hydrocortisone exposure and reduced efficacy of hydrocortisone Details Primidone Hydromorphone Injection Dilaudid Increased risk of respiratory and CNS depression Details Primidone Hydromorphone Rectal available generically Increased risk of respiratory and CNS depression Details

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Educational information only, not medical advice. Always confirm interactions with your pharmacist or prescriber before making any change to your medications.