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Pronunciation
(PRI mi done)
Generic Available (U.S.)
Yes
Index Terms
Medication Guide
An FDA-approved patient medication guide, which is available with the product information and at http://www.fda.gov/downloads/Drugs/DrugSafety/UCM222370.pdf, must be dispensed with this medication.
REMS Components
Mysoline®: Released from REMS requirement 8/10/2011
Brand Names: U.S.
Brand Names: Canada
Pharmacologic Category
Pharmacologic Category Synonyms
Use: Labeled Indications
Management of grand mal, psychomotor, and focal seizures
Use: Unlabeled
Benign familial tremor (essential tremor)
Pregnancy Considerations
Primidone and its metabolites (PEMA, phenobarbital, and p-hydroxyphenobarbital) cross the placenta; neonatal serum concentrations at birth are similar to those in the mother. Withdrawal symptoms may occur in the neonate and may be delayed due to the long half-life of primidone and its metabolites. Use may be associated with birth defects and adverse events; the use of folic acid throughout pregnancy and vitamin K during the last month of pregnancy is recommended. Epilepsy itself, number of medications, genetic factors, or a combination of these probably influence the teratogenicity of anticonvulsant therapy.Patients exposed to primidone during pregnancy are encouraged to enroll themselves into the NAAED Pregnancy Registry by calling 1-888-233-2334. Additional information is available at www.aedpregnancyregistry.org.
Lactation
Enters breast milk/not recommended (AAP recommends use “with caution”; AAP 2001 update pending)
Breast-Feeding Considerations
Primidone and its metabolites (PEMA, phenobarbital, and p-hydroxyphenobarbital) are found in breast milk (variable concentrations). The manufacturer recommends discontinuing breast-feeding if undue drowsiness and somnolence occur in the newborn.
Contraindications
Hypersensitivity to phenobarbital; porphyria
Warnings/Precautions
Concerns related to adverse effects:
• CNS depression: May cause CNS depression, which may impair physical or mental abilities; patients must be cautioned about performing tasks which require mental alertness (eg, operating machinery or driving).
• Suicidal ideation: Pooled analysis of trials involving various antiepileptics (regardless of indication) showed an increased risk of suicidal thoughts/behavior (incidence rate: 0.43% treated patients compared to 0.24% of patients receiving placebo); risk observed as early as 1 week after initiation and continued through duration of trials (most trials ≤24 weeks). Monitor all patients for notable changes in behavior that might indicate suicidal thoughts or depression; notify healthcare provider immediately if symptoms occur.
Disease-related concerns:
• Depression: Use with caution in patients with depression or suicidal tendencies.
• Hepatic impairment: Use with caution in patients with hepatic impairment.
• Hypoadrenalism: Use with caution in patients with hypoadrenalism.
• Renal impairment: Use with caution in patients with renal impairment.
• Respiratory disease: Use with caution in patients with respiratory disease.
• Substance abuse: Use with caution in patients with a history of drug abuse; potential for drug dependency exists. Tolerance or psychological and physical dependence may occur with prolonged use.
Concurrent drug therapy issues:
• Sedatives: Effects with other sedative drugs or ethanol may be potentiated.
Special populations:
• Debilitated patients: Use with caution in patients who are debilitated; may cause paradoxical responses.
• Elderly: Use with caution in the elderly; may cause paradoxical responses.
• Pediatrics: Use with caution in children; may cause paradoxical responses. Primidone's metabolite, phenobarbital, has been associated with cognitive deficits in children.
Other warnings/precautions:
• Acute pain: Do not administer to patients in acute pain.
• Withdrawal: Anticonvulsants should not be discontinued abruptly because of the possibility of increasing seizure frequency; therapy should be withdrawn gradually to minimize the potential of increased seizure frequency, unless safety concerns require a more rapid withdrawal.
Adverse Reactions
Frequency not defined.
Central nervous system: Ataxia, drowsiness, emotional disturbances, fatigue, hyperirritability, suicidal ideation, vertigo
Dermatologic: Morbilliform skin eruptions
Gastrointestinal: Anorexia, nausea, vomiting
Genitourinary: Impotence
Hematologic: Agranulocytosis, granulocytopenia, megaloblastic anemia (idiosyncratic), red cell aplasia/hypoplasia
Ocular: Diplopia, nystagmus
Metabolism/Transport Effects
Induces CYP1A2 (strong), CYP2B6 (strong), CYP2C8 (strong), CYP2C9 (strong), CYP3A4 (strong)
Drug Interactions
Alcohol (Ethyl): CNS Depressants may enhance the CNS depressant effect of Alcohol (Ethyl). Risk C: Monitor therapy
ARIPiprazole: CYP3A4 Inducers may decrease the serum concentration of ARIPiprazole. Management: Double aripiprazole dose when initiating concomitant therapy with a CYP3A4 inducer (e.g., carbamazepine). Monitor response and adjust aripiprazole dose as clinically indicated. If CYP3A4 inducer is discontinued, reduce aripiprazole dose to 10-15 mg/day. Risk D: Consider therapy modification
Barbiturates: Primidone may enhance the adverse/toxic effect of Barbiturates. Primidone is converted to phenobarbital, and thus becomes additive with existing barbiturate therapy. Risk C: Monitor therapy
Bendamustine: CYP1A2 Inducers (Strong) may decrease the serum concentration of Bendamustine. Concentrations of active metabolites may be increased. Risk C: Monitor therapy
Boceprevir: Primidone may decrease the serum concentration of Boceprevir. Risk X: Avoid combination
Bortezomib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Bortezomib. Risk X: Avoid combination
Brentuximab Vedotin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Brentuximab Vedotin. Specifically, concentrations of the active monomethyl auristatin E (MMAE) component may be decreased. Risk C: Monitor therapy
Carbonic Anhydrase Inhibitors: May enhance the adverse/toxic effect of Primidone. Specifically, osteomalacia and rickets. Carbonic Anhydrase Inhibitors may decrease the serum concentration of Primidone. Exceptions: Brinzolamide; Dorzolamide. Risk C: Monitor therapy
Clarithromycin: CYP3A4 Inducers (Strong) may increase serum concentrations of the active metabolite(s) of Clarithromycin. Clarithromycin may increase the serum concentration of CYP3A4 Inducers (Strong). CYP3A4 Inducers (Strong) may decrease the serum concentration of Clarithromycin. Risk D: Consider therapy modification
CNS Depressants: May enhance the adverse/toxic effect of other CNS Depressants. Exceptions: Levocabastine (Nasal). Risk C: Monitor therapy
Corticosteroids (Systemic): Primidone may decrease the serum concentration of Corticosteroids (Systemic). Risk C: Monitor therapy
Crizotinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Crizotinib. Risk X: Avoid combination
CYP1A2 Substrates: CYP1A2 Inducers (Strong) may increase the metabolism of CYP1A2 Substrates. Risk C: Monitor therapy
CYP2B6 Substrates: CYP2B6 Inducers (Strong) may increase the metabolism of CYP2B6 Substrates. Risk C: Monitor therapy
CYP2C8 Substrates: CYP2C8 Inducers (Strong) may increase the metabolism of CYP2C8 Substrates. Risk C: Monitor therapy
CYP2C9 Substrates: CYP2C9 Inducers (Strong) may increase the metabolism of CYP2C9 Substrates. Risk C: Monitor therapy
CYP3A4 Substrates: CYP3A4 Inducers (Strong) may increase the metabolism of CYP3A4 Substrates. Risk C: Monitor therapy
Dasatinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Dasatinib. Management: Avoid when possible. If such a combination cannot be avoided, consider increasing dasatinib dose and monitor clinical response and toxicity closely. Risk D: Consider therapy modification
Dexmethylphenidate: May increase serum concentrations of the active metabolite(s) of Primidone. Specifically, phenobarbital concentrations could become elevated. Dexmethylphenidate may increase the serum concentration of Primidone. Risk C: Monitor therapy
Diclofenac: CYP2C9 Inducers (Strong) may decrease the serum concentration of Diclofenac. Risk C: Monitor therapy
Dienogest: CYP3A4 Inducers (Strong) may decrease the serum concentration of Dienogest. Management: Avoid use of dienogest for contraception when using medications that induce CYP3A4 and for at least 28 days after discontinuation of a CYP3A4 inducer. An alternative form of contraception should be used during this time. Risk X: Avoid combination
Divalproex: May decrease the metabolism of Primidone. Primidone may decrease the serum concentration of Divalproex. Risk C: Monitor therapy
Dronedarone: CYP3A4 Inducers (Strong) may decrease the serum concentration of Dronedarone. Risk X: Avoid combination
Droperidol: May enhance the CNS depressant effect of CNS Depressants. Management: Consider dose reductions of droperidol or of other CNS agents (e.g., opioids, barbiturates) with concomitant use. Risk D: Consider therapy modification
Everolimus: CYP3A4 Inducers (Strong) may decrease the serum concentration of Everolimus. Management: Avoid concurrent use of strong CYP3A4 inducers, but if strong CYP3A4 inducers cannot be avoided, consider gradually (in 5 mg increments) increasing the everolimus dose from 10 mg/day to 20 mg/day (adult doses). Risk X: Avoid combination
Exemestane: CYP3A4 Inducers (Strong) may decrease the serum concentration of Exemestane. Management: Exemestane prescribing information recommends using an increased dose (50 mg/day) in patients receiving concurrent strong CYP3A4 inducers. Monitor patients closely for evidence of toxicity and/or inadequate clinical response. Risk D: Consider therapy modification
Felbamate: May increase serum concentrations of the active metabolite(s) of Primidone. Specifically, phenobarbital concentrations may increase. Primidone may decrease the serum concentration of Felbamate. Management: In patients receiving primidone, initiate felbamate at 1200 mg/day in divided doses 3-4 times daily and reduce primidone dose by 20%. Monitor for increased phenobarbital concentrations/effects and decreased felbamate concentrations/effects. Risk D: Consider therapy modification
Folic Acid: May decrease the serum concentration of Primidone. Additionally, folic acid may decrease concentrations of active metabolites of primidone (e.g., phenobarbital). Risk C: Monitor therapy
Fosphenytoin: May increase the metabolism of Primidone. The ratio of primidone:phenobarbital is thus changed. Risk C: Monitor therapy
Gefitinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Gefitinib. Management: In the absence of severe adverse drug reactions, consider increasing gefitinib dose to 500 mg daily in patients receiving strong CYP3A4 inducers. Carefully monitor clinical response and development of adverse reactions. Risk D: Consider therapy modification
GuanFACINE: CYP3A4 Inducers (Strong) may decrease the serum concentration of GuanFACINE. Management: Consider increasing the guanfacine dose (within the labeled dosage range) when such a combination is used. Risk D: Consider therapy modification
HydrOXYzine: May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy
Imatinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Imatinib. Management: Avoid concurrent use of imatinib with strong CYP3A4 inducers when possible. If such a combination must be used, increase imatinib dose by at least 50% and monitor the patient's clinical response closely. Risk D: Consider therapy modification
Ixabepilone: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ixabepilone. Management: Avoid this combination whenever possible. If this combination must be used, a gradual increase in ixabepilone dose from 40 mg/m2 to 60 mg/m2 (given as a 4-hour infusion), as tolerated, should be considered. Risk D: Consider therapy modification
Ketorolac: May diminish the therapeutic effect of Anticonvulsants. Risk C: Monitor therapy
Ketorolac (Nasal): May diminish the therapeutic effect of Anticonvulsants. Risk C: Monitor therapy
Ketorolac (Systemic): May diminish the therapeutic effect of Anticonvulsants. Risk C: Monitor therapy
LamoTRIgine: Primidone may decrease the serum concentration of LamoTRIgine. Management: Adjust dose per lamotrigine prescribing information guidelines during primidone treatment. Monitor for decreased concentration/effect if primidone is initiated/dose increased or increased concentration/effect if primidone is discontinued/dose decreased. Risk D: Consider therapy modification
Lapatinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Lapatinib. Management: If therapy overlap cannot be avoided, consider titrating lapatinib gradually from 1,250 mg/day up to 4,500 mg/day (HER2 positive metastatic breast cancer) or 1,500 mg/day up to 5,500 mg/day (hormone receptor/HER2 positive breast cancer) as tolerated. Risk X: Avoid combination
Leucovorin Calcium-Levoleucovorin: May decrease the serum concentration of Primidone. Additionally, leucovorin/levoleucovorin may decrease concentrations of active metabolites of primidone (e.g., phenobarbital). Risk C: Monitor therapy
Levomefolate: May decrease serum concentrations of the active metabolite(s) of Primidone. Levomefolate may decrease the serum concentration of Primidone. Risk C: Monitor therapy
Linagliptin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Linagliptin. Management: Strongly consider using an alternative to any strong CYP3A4 inducer in patients who are being treated with linagliptin. If this combination is used, monitor patients closely for evidence of reduced linagliptin effectiveness. Risk D: Consider therapy modification
Lurasidone: CYP3A4 Inducers (Strong) may decrease the serum concentration of Lurasidone. Risk X: Avoid combination
Maraviroc: CYP3A4 Inducers (Strong) may decrease the serum concentration of Maraviroc. Management: Increase maraviroc adult dose to 600 mg twice daily when used with strong CYP3A4 inducers. This does not apply to patients also receiving strong CYP3A4 inhibitors. Do not use maraviroc with strong CYP3A4 inducers in patients with Clcr less than 30 mL/min. Risk D: Consider therapy modification
Mefloquine: May diminish the therapeutic effect of Anticonvulsants. Mefloquine may decrease the serum concentration of Anticonvulsants. Management: Mefloquine is contraindicated for malaria prophylaxis in persons with a history of convulsions. Monitor anticonvulsant concentrations and treatment response closely with concurrent use. Risk D: Consider therapy modification
Methotrimeprazine: CNS Depressants may enhance the CNS depressant effect of Methotrimeprazine. Methotrimeprazine may enhance the CNS depressant effect of CNS Depressants. Management: Reduce adult dose of CNS depressant agents by 50% with initiation of concomitant methotrimeprazine therapy. Further CNS depressant dosage adjustments should be initiated only after clinically effective methotrimeprazine dose is established. Risk D: Consider therapy modification
Methylfolate: May decrease the serum concentration of Primidone. Risk C: Monitor therapy
Methylphenidate: May increase serum concentrations of the active metabolite(s) of Primidone. Specifically, phenobarbital concentrations could become elevated. Methylphenidate may increase the serum concentration of Primidone. Risk C: Monitor therapy
NIFEdipine: CYP3A4 Inducers (Strong) may decrease the serum concentration of NIFEdipine. Management: Consider alternatives to nifedipine for patients who are using strong CYP3A4 inducers. At least one specific brand of nifedipine (Adalat CC) lists this combination as contraindicated. Risk D: Consider therapy modification
Nilotinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Nilotinib. Risk X: Avoid combination
Nisoldipine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Nisoldipine. Risk X: Avoid combination
Pazopanib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Pazopanib. Risk X: Avoid combination
Phenytoin: May increase the metabolism of Primidone. The ratio of primidone:phenobarbital is thus changed. Risk C: Monitor therapy
Praziquantel: CYP3A4 Inducers (Strong) may decrease the serum concentration of Praziquantel. Management: Avoid concomitant use of praziquantel with strong CYP3A4 inducers. Discontinue rifampin 4 weeks prior to initiation of praziquantel therapy. Rifampin may be resumed the day following praziquantel completion. Risk X: Avoid combination
QuiNIDine: Primidone may decrease the serum concentration of QuiNIDine. Risk C: Monitor therapy
Ranolazine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ranolazine. Risk X: Avoid combination
Rilpivirine: Primidone may decrease the serum concentration of Rilpivirine. Risk X: Avoid combination
Rivaroxaban: CYP3A4 Inducers (Strong) may decrease the serum concentration of Rivaroxaban. Risk X: Avoid combination
Roflumilast: CYP3A4 Inducers (Strong) may decrease the serum concentration of Roflumilast. Management: Roflumilast U.S. prescribing information recommends against combining strong CYP3A4 inducers with roflumilast. The Canadian product monograph makes no such recommendation but notes that such agents may reduce roflumilast therapeutic effects. Risk X: Avoid combination
RomiDEPsin: CYP3A4 Inducers (Strong) may decrease the serum concentration of RomiDEPsin. Risk X: Avoid combination
Rufinamide: Primidone may decrease the serum concentration of Rufinamide. Risk C: Monitor therapy
Saxagliptin: CYP3A4 Inducers may decrease the serum concentration of Saxagliptin. Risk C: Monitor therapy
Selective Serotonin Reuptake Inhibitors: CNS Depressants may enhance the adverse/toxic effect of Selective Serotonin Reuptake Inhibitors. Specifically, the risk of psychomotor impairment may be enhanced. Risk C: Monitor therapy
SORAfenib: CYP3A4 Inducers (Strong) may decrease the serum concentration of SORAfenib. Risk X: Avoid combination
SUNItinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of SUNItinib. Management: Avoid when possible. If such a combination cannot be avoided, consider increasing sunitinib dose and monitor clinical response and toxicity closely. Risk D: Consider therapy modification
Tadalafil: CYP3A4 Inducers (Strong) may decrease the serum concentration of Tadalafil. Management: Erectile dysfunction: monitor for decreased effectiveness - no standard dose adjustments recommended. Avoid use of tadalafil for pulmonary arterial hypertension in patients receiving a strong CYP3A4 inducer. Risk D: Consider therapy modification
Ticagrelor: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Ticagrelor. CYP3A4 Inducers (Strong) may decrease the serum concentration of Ticagrelor. Risk X: Avoid combination
Tolvaptan: CYP3A4 Inducers (Strong) may decrease the serum concentration of Tolvaptan. Management: If concurrent use is necessary, increased doses of tolvaptan (with close monitoring for toxicity and clinical response) may be needed. Risk X: Avoid combination
Toremifene: CYP3A4 Inducers (Strong) may decrease the serum concentration of Toremifene. Risk X: Avoid combination
Treprostinil: CYP2C8 Inducers (Strong) may decrease the serum concentration of Treprostinil. Risk C: Monitor therapy
Ulipristal: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ulipristal. Risk C: Monitor therapy
Valproic Acid: May decrease the metabolism of Primidone. More specifically, the metabolism of phenobarbital, primidone's primary active metabolite, would be decreased. Primidone may decrease the serum concentration of Valproic Acid. Risk C: Monitor therapy
Vandetanib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Vandetanib. Risk X: Avoid combination
Vemurafenib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Vemurafenib. Risk C: Monitor therapy
Zuclopenthixol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Zuclopenthixol. Risk C: Monitor therapy
Ethanol/Nutrition/Herb Interactions
Ethanol: May increase CNS depression; monitor for increased effects with coadministration. Caution patients about effects.
Food: Protein-deficient diets increase duration of action of primidone.
Herb/Nutraceutical: Avoid valerian, St John's wort, kava kava, gotu kola (may increase CNS depression).
Storage
Store at 20°C to 25°C (68°F to 77°F).
Mechanism of Action
Decreases neuron excitability, raises seizure threshold similar to phenobarbital; primidone has two active metabolites, phenobarbital and phenylethylmalonamide (PEMA); PEMA may enhance the activity of phenobarbital
Pharmacodynamics/Kinetics
Absorption: 60% to 80%
Distribution: Adults: Vd: 0.6 L/kg
Protein binding: 30%
Metabolism: Hepatic to phenobarbital (active) by oxidation and to phenylethylmalonamide (PEMA; active) by scission of the heterocyclic ring
Half-life elimination (age dependent): Primidone: Mean: 5-15 hours (variable); PEMA: 16 hours (variable)
Time to peak, serum: ~3 hours (variable)
Excretion: Urine (40% as unchanged drug; the remainder is unconjugated PEMA, phenobarbital and its metabolites)
Dosage
Oral:
Seizure disorders:
Children <8 years: Initial: Days 1-3: 50 mg/day given at bedtime; days 4-6: 50 mg twice daily; days 7-9: 100 mg twice daily; usual dose: 375-750 mg/day in 3-4 divided doses (10-25 mg/kg/day)
Children ≥8 years and Adults: Days 1-3: 100-125 mg/day at bedtime; days 4-6: 100-125 twice daily; days 7-9: 100-125 mg 3 times daily; usual dose: 750-1500 mg/day in divided doses 3-4 times/day with maximum dosage of 2 g/day
Patients already receiving other anticonvulsants: Initial: 100-125 mg at bedtime; gradually increase to maintenance dose as other drug is gradually decreased, continue until desired level obtained or other drug completely withdrawn. If goal is monotherapy, conversion should be completed over ≥2 weeks.
Essential tremor (unlabeled use): Adults: Initial 12.5-25 mg/day at bedtime; titrate up to 250 mg/day in 1-2 divided doses; doses up to 750 mg/day may be beneficial
Dosing interval in renal impairment: Adults (Aronoff, 2007): Note: Avoid in renal failure if possible; due to active metabolites with long half-lives and complex kinetics:
Clcr ≥50 mL/minute: Administer every 12 hours
Clcr 10-50 mL/minute: Administer every 12-24 hours
Clcr <10 mL/minute: Administer every 24 hours
Hemodialysis: Administer dose postdialysis
Monitoring Parameters
Serum primidone and phenobarbital concentration, neurological status. Due to CNS effects, monitor closely when initiating drug in elderly. Monitor CBC and sequential multiple analysis-12 (SMA-12) at 6-month intervals to compare with baseline obtained at start of therapy. Monitor for suicidality (eg, suicidal thoughts, depression, behavioral changes). Since elderly metabolize phenobarbital at a slower rate than younger adults, it is suggested to measure both primidone and phenobarbital levels together.
Reference Range
Therapeutic: Children <5 years: 7-10 mcg/mL (SI: 32-46 micromole/L); Adults: 5-12 mcg/mL (SI: 23-55 micromole/L); toxic effects rarely present with levels <10 mcg/mL (SI: 46 micromole/L) if phenobarbital concentrations are low. Dosage of primidone is adjusted with reference mostly to the phenobarbital level; Toxic: >15 mcg/mL (SI: >69 micromole/L)
Dietary Considerations
Folic acid: Low erythrocyte and CSF folate concentrations. Megaloblastic anemia has been reported. To avoid folic acid deficiency and megaloblastic anemia, some clinicians recommend giving patients on anticonvulsants prophylactic doses of folic acid and cyanocobalamin.
Patient Education
While using this medication, do not use alcohol. Maintain adequate hydration unless instructed to restrict fluid intake. You may experience drowsiness, dizziness, blurred vision, nausea, vomiting, loss of appetite, or impotence (reversible). Wear identification of epileptic status and medications. Report behavioral or CNS changes (confusion, depression, increased sedation, excitation, headache, insomnia, or lethargy), suicide ideation, muscle weakness or tremors, unusual bruising or bleeding (mouth, urine, stool), or worsening of seizure activity or loss of seizure control.
Geriatric Considerations
Due to CNS effects, monitor closely when initiating drug in elderly. Monitor CBC at 6-month intervals to compare with baseline obtained at start of therapy. Since elderly metabolize phenobarbital at a slower rate than younger adults, it is suggested to measure both primidone and phenobarbital serum concentrations together. Adjust dose for renal function in elderly when initiating or changing dose.
Dental Health: Effects on Dental Treatment
No significant effects or complications reported
Dental Health: Vasoconstrictor/Local Anesthetic Precautions
No information available to require special precautions
Nursing: Physical Assessment/Monitoring
Monitor for signs and symptoms of depression or suicide ideation. Taper dosage slowly when discontinuing. Teach patient safety and seizure precautions.
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, oral: 50 mg, 250 mg
Mysoline®: 50 mg, 250 mg [scored]
Pricing: U.S. (www.drugstore.com)
Tablets (Mysoline)
50 mg (90): $194.24
250 mg (30): $209.99
Tablets (Primidone)
50 mg (90): $39.99
250 mg (90): $69.99
References
American Academy of Pediatrics Committee on Drugs, "Transfer of Drugs and Other Chemicals Into Human Milk," Pediatrics, 2001, 108(3):776-89.
Aronoff GR, Bennett WM, Berns JS, et al, Drug Prescribing in Renal Failure: Dosing Guidelines for Adults and Children, 5th ed. Philadelphia, PA: American College of Physicians; 2007, p 91.
Chen JJ and Swope DM, “Essential Tremor: Diagnosis and Treatment,” Pharmacotherapy, 2003, 23(9):1105-22.
Louis ED, “Clinical Practice. Essential Tremor,” N Engl J Med, 2001, 345(12):887-91.
McNamara JO, “Drugs Effective in the Therapy of the Epilepsies,” Gardman JG, Limbird LE, eds, Goodman and Gilman's The Pharmacological Basis of Therapeutics, 10th ed, New York, NY: McGraw-Hill, 2001:532.
Nau H, Rating D, Häuser I, et al, "Placental Transfer and Pharmacokinetics of Primidone and Its Metabolites Phenobarbital, PEMA and Hydroxyphenobarbital in Neonates and Infants of Epileptic Mothers," Eur J Clin Pharmacol, 1980, 18(1):31-42.
Pahwa R and Lyons KE, “Essential Tremor: Differential Diagnosis and Current Therapy,” Am J Med, 2003, 115(2):134-42.
Porter RJ, Meldrum BD, “Antiepileptic Drugs,” Katzung BG, ed, Basic & Clinical Pharmacology, 6th ed, East Norwalk, CT: Appleton & Lange, 1995:369.
Schwankhaus JD, Kattah JC, Lux WE, et al, “Primidone/Phenobarbital-Induced Periodic Alternating Nystagmus,” Ann Ophthalmol, 1989, 21(6):230-2.
International Brand Names
Lexi-Comp.com
Last full review/revision January 2012
Content last modified January 2012
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