Adult Dosing
Grand mal, psychomotor and focal epileptic seizures
- If no previous anticonvulsants: Start 100-125 mg PO qhs x 3 days, then 100-125 mg bid x 3 days, then 100-125 mg tid x 3 days, followed by maintenance dose of 250 mg tid-qid. [Max: 2000 mg/day]
- If already receiving anticonvulsants: Start 100-125 mg PO qhs, gradually increasing dose to maintenance level as other drug is gradually decreased. Complete switch to primidone should take no less than 2 weeks
Management of essential tremor (Not FDA approved)
- Adults: Start: 12.5-25 mg PO qhs; increase qwk (by 12.5-25 mg/day) to effective maintenance dose. [Max: 750 mg/day]
Pediatric Dosing
Grand mal, psychomotor and focal epileptic seizures
Child >8 yrs
- If no previous anticonvulsants: Start 100-125 mg PO qhs for 3 days, then 100-125 mg bid for 3 days, then 100-125 mg tid for 3 days, followed by maintenance dose of 250 mg tid-qid. [Max: 2000 mg/day]
- If already receiving anticonvulsants: Start 100-125 mg PO qhs, gradually increasing dose to maintenance level as other drug is gradually decreased. Complete switch to primidone should take no less than 2 weeks
Child <8 yrs
- Dose 10–25 mg/kg/day in divided doses. Start 50 mg PO qhs for 3 days, then 50 mg bid for 3 days, then 100 mg bid for 3 days, followed by maintenance dose of 125–250 mg tid (10-25 mg/kg/day in divided doses). [Max: 2000 mg/day]
[Outline]
Renal Dose Adjustment (Based on CrCl)
- Renal Impairment
- > 50 mL/min: Give q8 hrs
- 10-50 mL/min: Give q8-12 hrs
- <10 mL/min: Give q12-24 hrs
Hepatic Dose Adjustment
- Hepatic impairment: Dosage adjustment not defined; caution advised
- Slowly taper to discontinue if at risk for physical dependence. Abrupt cessation can cause a withdrawal syndrome or precipitate seizures
- Monitor CrCl at baseline and CBC, SMA-12 test every six months
- Patients treated with any antiepilieptic medication for any indication should be monitored for the emergence or worsening of depression, suicidal thoughts or behavior, and/or any unusual changes in mood. Antiepilieptic medications have been associated with an increased risk of these conditions.
Cautions: Use cautiously in
- Renal impairment
- Hepatic impairment
- Impaired pulmonary function
- Elderly population
- Hx of depression
- Pregnancy
- Lactation
Pregnancy Category:D
Breastfeeding: Possibly unsafe; primidone and its metabolites are excreted in breastmilk often near or in therapeutic range. Symptoms of sedation and poor nursing have been reported. Monitor infants for drowsiness, adequate nursing and weight gain, and developmental milestones (especially in younger, exclusively breastfed infants, and when combinations of anticonvulsant drugs are used). This drug should be used with caution based upon data from AAP Policy Guidelines (available at http://aappolicy.aappublications.org/cgi/content/full/pediatrics;108/3/776) and based upon LactMed database (available at http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT last accessed 13 January 2011). Manufacturer recommends discontinuation of breastfeeding if undue somnolence and drowsiness is noted in infants.
Pricing data from www.DrugStore.com in U.S.A.
- Mysoline 250 MG TABS [Bottle] (VALEANT)
30 mg = $218.98
90 mg = $633.99 - Mysoline 50 MG TABS [Bottle] (VALEANT)
90 mg = $179.99
270 mg = $519.96 - Primidone 50 MG TABS [Bottle] (LANNETT)
90 mg = $39.99
270 mg = $109.97 - Primidone 250 MG TABS [Bottle] (AMNEAL PHARMACEUTICALS)
90 mg = $69.99
270 mg = $191.98
Warning: This pricing information is subject to change at the sole discretion of DS Pharmacy. For the most current and up-to-date pricing information, please visit drugstore.com.
