Anticonvulsants (Adult dosing)
carbamazepine
Tegretol ®		Adults: Epilepsy: initially 200 mg twice daily. Increase by 200 mg/day at weekly intervals until therapeutic levels are obtained. Usual range: 800-1200mg/day  divided in 3 to 4 doses. Maximum recommended dose: 1600 mg/day. Doses as high as 2.4 grams/day have been given.    Trigeminal or glossopharyngeal neuralgia: Oral: Initial: 100 mg twice daily with food, gradually increasing in increments of 100 mg twice daily as needed.  Maintenance: Usual: 400-800 mg daily in 2 divided doses; maximum dose: 1200 mg/day.

Supplied:  Extended release cap: 100 mg, 200 mg, 300 mg.
Oral suspension: 100 mg/5 ml (10 ml, 450 ml).
Tablet: 200 mg.  Chewable tab: 100 mg.  ER Tab: 100 mg, 200 mg, 400 mg.
clonazepam Klonopin ® Start 0.5 mg orally three times daily.  Maximum: 20 mg/day.   [Supplied: 0.5,1, 2mg tabs]
diazepam
Valium ®		Adults: Status epilepticus: IV: 5-10 mg every 10-20 minutes, up to 30 mg in an 8-hour period; may repeat in 2-4 hours if necessary.  Anxiety/sedation/skeletal muscle relaxation:  Oral: 2-10 mg 2 to 4 times/day. IM, IV: 2-10 mg, may repeat in 3-4 hours if needed.
ethosuximide Zarontin ®Initially, 250mg orally twice a day.  Maintenance 20-30mg/kg/day in divided doses twice daily.  Maximum:  1.5g/day
felbamate Felbatol ®Start:  400mg orally three times daily. Range: 1200 to 3600 mg daily (divided in 3 to 4 doses).   Supplied: [400 , 600 mg  tablets]
fosphenytoin Cerebyx ® Load: 15-20 mg/kg IM/IV. Max rate: 100-150 mg/min. Maintenance: 4 to 6 mg/kg/day divided doses every 8 to 12 hours.
gabapentin (Neurontin ®):General dosing: Start 300mg at bedtime. Increase over few days to 300 to 600mg orally three times daily. Maximum: 3600mg/day.
Dosing (Adults): 
Anticonvulsant: Oral:  Initial: 300 mg 3 times/day, if necessary the dose may be increased up to 1800 mg/day.    Maintenance: 900-1800 mg/day administered in 3 divided doses; doses of up to 2400 mg/day have been tolerated in long-term clinical studies; up to 3600 mg/day has been tolerated in short-term studies.  Postherpetic neuralgia: Day 1: 300 mg, Day 2: 300 mg twice daily, Day 3: 300 mg 3 times/day; dose may be titrated as needed for pain relief (range: 1800-3600 mg/day, daily doses >1800 mg do not generally show greater benefit)
Renal dosing:   
Crcl > 60 ml/minute: 300-1200 mg 3 times/day.
Crcl >30-59 ml/minute:200-700 mg twice/day.
Crcl >15-29 ml/minute: 200-700 mg/day.  
Crcl 15 ml/minute: 100-300mg/day.
Crcl <15 ml/minute: Reduce daily dose in proportion to creatinine clearance.

Supplied: Capsule: 100 mg, 300 mg, 400 mg.  Oral Solution: 250 mg/5 ml (480 ml).  Tablet: 100 mg, 300 mg, 400 mg.
levetiracetam Keppra ® Adjunctive therapy in the treatment of partial-onset seizures. Start 500mg orally twice daily. Maximum: 1500 mg orally twice daily.   (May adjust dose every 2 weeks).   There is no evidence that doses greater than 3000 mg/day confer additional benefit.  Renal dosing:  
CRCL 50-80:  500 to 1,000 q12h.  
(30-50 ml/min): 250 to 750 q12h.  
(CRCL <30 ml/min):  250 to 500 q12h.  
( ESRD - dialysis):  500 to 1,000mg q24h.  Following dialysis, a 250 to 500 mg supplemental dose is recommended.  
[Supplied: 250, 500, 750mg tablets] 
lamotrigine Lamictal ®Dosing (Adults):  
Adjunctive tx of Lennox-Gastaut or partial seizures: Patients receiving AED regimens containing valproic acid: Initial dose: 25 mg every other day x 2 weeks, then 25 mg qd x 2 weeks. Dose may be increased by 25-50 mg qd x 1-2 weeks in order to achieve maintenance dose. Maintenance dose: 100-400 mg/day in 1-2 divided doses (usual range 100-200 mg/day).    Patients receiving enzyme-inducing AED regimens without valproic acid: Initial dose: 50 mg/day x 2 weeks, then 100 mg in 2 doses x 2 weeks; thereafter, daily dose can be increased by 100 mg every 1-2 weeks to be given in 2 divided doses. Usual maintenance dose: 300-500 mg/day in 2 divided doses.

Bipolar disorder: 25 mg/day x 2 weeks, followed by 50 mg/day x 2 weeks, followed by 100 mg/day x 1 week. Thereafter, daily dosage may be increased to 200 mg/day. Patients receiving valproic acid: Initial: 25 mg every other day x 2 weeks, followed by 25 mg/day x 2 weeks, followed by 50 mg/day x 1 week, followed by 100 mg/day (target dose) thereafter. Note: If valproate is discontinued, increase daily lamotrigine dose in 50 mg increments at weekly intervals until daily dosage of 200 mg is attained. Patients receiving enzyme-inducing drugs: Initial: 50 mg/day x 2 weeks, followed by 100 mg/day (in divided doses) x 2 weeks, followed by 200 mg/day (in divided doses) x 1 week, followed by 300 mg/day (in divided doses) x 1 week. May increase to 400 mg/day (in divided doses) during week 7 and thereafter. Note: If carbamazepine (or other enzyme-inducing drug) is discontinued, decrease daily lamotrigine dose in 100 mg increments at weekly intervals until daily dosage of 200 mg is attained.

Possible life-threatening rash. 
[Supplied: 25, 100, 150, 200mg tablets]
lorazepam 
Ativan ®
 
  		Dosing (Adults):  Antiemetic: Oral, IV:  0.5-2 mg every 4-6 hours as needed.    Anxiety and sedation: Oral: 1-10 mg/day in 2-3 divided doses; usual dose: 2-6 mg/day in divided doses; initial dose should not exceed 2 mg in debilitated patients.  Insomnia: Oral: 2-4 mg at bedtime.     Preoperative:  IM: 0.05 mg/kg administered 2 hours before surgery; maximum: 4 mg/dose.  IV: 0.044 mg/kg 15-20 minutes before surgery; usual maximum: 2 mg/dose.   Status epilepticus: IV: 4 mg/dose given slowly over 2-5 minutes; may repeat in 10-15 minutes; usual maximum dose: 8 mg.     Rapid tranquilization of agitated patient (administer every 30-60 minutes):   Oral: 1-2 mg. IM: 0.5-1 mg.   Agitation in the ICU patient (unlabeled):  IV: 0.02-0.06 mg/kg every 2-6 hours. Alternatively - IV infusion: 0.01-0.1 mg/kg/hour.

Onset:   Hypnosis: IM: 20-30 minutes. Sedation: IV: 5-20 minutes. Anticonvulsant: IV: 5 minutes, oral: 30-60 minutes.
Duration: 6-8 hours.

Supplied:  Injection: 2 mg/ml (1 ml, 10 ml); 4 mg/ml (1 ml, 10 ml). Oral concentrate: 2 mg/ml (30 ml). Tablet: 0.5 mg, 1 mg, 2 mg.
oxcarbazepine Trileptal ® Adjunctive treatment and monotherapy in the treatment of partial seizures in adults and as adjunctive treatment for partial seizures in children ages 4-16.   Adults (initial dosing) adjunctive therapy: 300mg orally twice daily.  If clinically indicated, the dose may be increased by a maximum of 600 mg/day at approximately weekly intervals.  Recommend dose: 600mg orally twice daily. 
Conversion to monotherapy:  Patients receiving concomitant anticonvulsants may be converted to monotherapy by initiating with 300mg orally twice daily while simultaneously initiating the reduction of the dose of the concomitant anticonvulsants. The concomitant anticonvulsants should be completely withdrawn over 3-6 weeks, while the maximum dose of Trileptal should be reached in about 2-4 weeks. Trileptal may be increased as clinically indicated by a maximum increment of 600 mg/day at approximately weekly intervals to achieve the recommended daily dose of 2400 mg/day. 
[Supplied: 150, 300, 600mg tabs]
phenobarbital: Dosing (Adults):  Sedation: Oral, IM: 30-120 mg/day in 2-3 divided doses.  Hypnotic: Oral, IM, IV, SQ: 100-320 mg at bedtime.  Preoperative sedation: IM: 100-200 mg 1-1.5 hours before procedure.   
Status epilepticus: Adults: 300-800 mg initially followed by 120-240 mg/dose at 20-minute intervals until seizures are controlled or a total dose of 20mg/kg.  (Maintenance):  1 to 3 mg/kg/day in divided doses or 50-100 mg 2 to 3 times/day.
Supplied: Tablet: 15 mg, 30 mg, 32 mg, 60 mg, 65 mg, 100 mg.
Elixir: 20 mg/5 ml (473 ml).    Injection:  65 mg/ml (1 ml); 130 mg/ml (1 ml).
phenytoin 
Dilantin ®		Loading Dose (IV): 10 - 20 mg/kg. Maximum  rate: 50 mg/min. Recommended infusion rate for adults: 40-50 mg/min. Elderly (>65): Recommended infusion rate: 20-25 mg/min.  
Oral loading: Give in 3 to 4 divided doses at q2h intervals. (Divided doses increase bioavailability as well as decrease potential for GI side effects such as N&V). The maximum single oral dose should not exceed 400 mg in order to minimize GI side effects and also increase absorption (decrease likelihood of concretions).  Maintenance: 4-6 mg/kg/day given in  2 to 3 divided doses. Equation used to estimate the dose required to increase current level to normal range if sub-therapeutic: [ 0.7 x IBW x (15 - current level)].
Oral suspension administration: Shake well prior to use. Divide the daily dose of phenytoin and withhold the administration of nutritional supplements for 1-2 hours before and after each phenytoin dose.

Sampling: 18 to 24 hours after the loading dose, and then every 5 to 7 days to assess trend. 
Average time to steady state: 10-14 days. Half-life: 7 to 42 hours (average = 24 hours).
Conversion to once daily dosing: Consider only after a divided dose regimen on extended phenytoin capsules is established. (Only extended release Dilantin caps are recommended for once daily administration.)  A patient should never receive a once daily dose of elixir or injection as maintenance.
When do you start the maintenance dose? The maintenance dose is started 18-24 hours after the loading dose.

Capsules/injection= 92% phenytoin (sodium salt).    Elixir/tabs=100% phenytoin.  
Equation used to estimate the dose required to increase current level to normal range if subtherapeutic: = [0.7 x IBW x (15 - current level) ] / 0.92* * (if capsules/injection used) 

Adjusted phenytoin concentration if low serum albumin 
= measured total concentration / [ (0.2 x albumin) + 0.1].

Renal failure: Cadjusted = Cmeasured / [ (0.1 x albumin) + 0.1) ]
pregabalin 
Lyrica ®		Dosing (Adults):  
Diabetic peripheral neuropathy: initial, 50 mg orally three times a day (150 mg/day) and may be increased to 100 mg orally three times a day (300 mg/day) within 1 week based on efficacy and tolerability.   
Postherpetic neuralgia: initial, 75 mg orally two times a day or 50 mg orally three times a day; may be increased to 300 mg/day within 1 week based on efficacy and tolerability.  (Maintenance): 75 to 150 mg orally two times a day or 50 to 100 mg orally three times a day (150 to 300 mg/day).  If patients do not experience sufficient pain relief following 2 to 4 weeks of treatment with 300 mg/day and are tolerating pregabalin -- may increase dose up to 300 mg two times a day, or 200 mg three times a day (600 mg/day).

Renal dosing:   
Crcl 30 to 60 ml/min: 75 to 300 mg/day in 2 to 3 divided doses. Crcl 15 to 30 ml/min: 25 to 150 mg/day given once daily or in 2 divided doses. 
Crcl < 15: 25 to 75 mg once daily.
hemodialysis: see package insert. 
Supplied: Oral Capsule: 25, 50, 75, 100, 150, 200, 225, 300 mg.
primidone
 Mysoline ®		 Start:100-125 mg orally at bedtime, increase over 10 days to 250mg orally 3  to 4 times daily.
tiagabine
Gabitril ®		Dosing (Adults): Partial seizures (adjunct):   Start:4 mg orally once daily x 1 week. May increase by 4-8 mg at weekly intervals until patient responds (Max: 56 mg daily in 2-4 divided doses).  Important Note: If patient is currently not receiving other enzyme-inducing anticonvulsant(s), lower starting doses are required based on the potential for much higher plasma levels.
[Supplied: 2, 4, 12, 16, 20mg tablets]
Warning: potential risk of seizures occurring in nonepileptic patients treated with Gabitril.
topiramate Topamax ® Dosing (Adults) 
  - Partial onset seizure and primary generalized tonic-clonic seizure:  Start: 25 mg twice daily then increase by 50mg/day (divided doses) once weekly up to 100 mg twice daily. Further increases may be made at 100 mg/day at weekly intervals up to the recommended maximum of 200 mg twice daily. 

 - Migraine prophylaxis: Start: 25 mg orally once daily (in the evening), titrated at weekly intervals in 25 mg increments, up to the recommended total daily dose of 100 mg/day given in 2 divided doses.
Renal dosing:  [crcl < 70 ml/min]:  Administer 50% of the usual dose and titrate slowly.
[Supplied: 15mg, 25mg capsules.   25, 50, 100, 200mg tablets]
valproic acid:
Depacon ® Depakene ® Depakote ® Delayed Release
Depakote ® ER 


PO: Administer with or immediately after meals to minimize GI irritation. Delayed-release divalproex sodium may cause less GI irritation than valproic acid capsules. 		Dosing (Adults) 
Seizures:  ORAL: Initially 10-15 mg/kg/day (orally) in 1-3 divided doses. Increase by 5-10 mg/kg/day q7 days until therapeutic levels are achieved. Maintenance: 30-60 mg/kg/day. Adult usual dose: 1000-2500 mg/day. 
IV: Administer as a 60-minute infusion (</= 20 mg/minute) with the same frequency as oral products; switch patient to oral products as soon as possible. Alternatively, rapid infusions have been given: </= 15 mg/kg over 5-10 minutes (1.5  to 3 mg/kg/minute).  Rectal (unlabeled): Dilute syrup 1:1 with water for use as a retention enema; loading dose: 17-20 mg/kg one time; maintenance: 10-15 mg/kg/dose every 8 hours.
Status epilepticus (unlabeled use): Loading dose: 15-25 mg/kg IV administered at 3 mg/kg/minute.  Maintenance dose: I.V. infusion: 1-4 mg/kg/hour; titrate dose as needed based upon patient response and evaluation of drug-drug interactions.

Mania: Oral: 750-1500 mg/day in divided doses; dose should be adjusted as rapidly as possible to desired clinical effect; a loading dose of 20 mg/kg may be used; maximum recommended dosage: 60 mg/kg/day.

Migraine prophylaxis: Oral:  Extended release tablets: 500 mg once daily for 7 days, then increase to 1000 mg once daily; adjust dose based on patient response; usual dosage range 500-1000 mg/day.  Delayed release tablets: 250 mg twice daily; adjust dose based on patient response, up to 1000 mg/day.
Administered orally. The recommended initial dose is 15 mg/kg/day orally, increasing at 1-week intervals by 5 to 10 mg/kg/day until seizures are controlled or side effects preclude further increases. Maximum recommended dose is 60 mg/kg/day. When the total daily dose exceeds 250 mg, it should be given in a divided regimen. A 500 mg enteric-coated capsule may be substituted for two 250 mg capsules. The frequency of adverse effects (particularly elevated liver enzymes) may increase with increasing dose. Therefore, the benefit gained by improved seizure control must be weighed against the increased incidence of adverse effects.
Note: Regular release and delayed release formulations are usually given in 2-4 divided doses/day, extended release formulation (Depakote® ER) is usually given once daily. Conversion to Depakote® ER from a stable dose of Depakote® may require an increase in the total daily dose between 8% and 20% to maintain similar serum concentrations (ER form has reduced bioavailability)

Supplied:  Note: Strength expressed as valproic acid
Valproic acid (Depakene®): 250 mg cap.
Capsule (sprinkles) as divalproex sodium (Depakote® Sprinkle®): 125 mg
Injection soln - valproate sodium (Depacon®): 100 mg/mL (5 mL) 
Syrup ( valproic acid) Depakene®: 250 mg/5 mL (480 mL)
Delayed release tablet - divalproex sodium (Depakote®): 125, 250, 500 mg
Extended release tab - divalproex sodium (Depakote® ER): 250, 500 mg

Therapeutic Range:
Epilepsy: 50-100 mcg/mL (SI: 350-690 µmol/L).
Mania: 50-125 mcg/mL (SI: 350-860 µmol/L). Conversion from DEPAKOTE to DEPAKOTE ER :
In adult patients and pediatric patients 10 years of age or older with epilepsy previously receiving DEPAKOTE, DEPAKOTE ER should be administered once-daily using a dose 8 to 20% higher than the total daily dose of DEPAKOTE (Table 5). For patients whose DEPAKOTE total daily dose can not be directly converted to DEPAKOTE ER, consideration may be given at the clinician's discretion to increase the patient's DEPAKOTE total daily dose to the next higher dosage before converting to the appropriate total daily dose of DEPAKOTE ER.
Dose Conversion
DEPAKOTE
Total Daily Dose (mg)		 DEPAKOTE ER
(mg)
500 -625* 750
750-875* 1000
1000 -1125* 1250
1250-1375 1500
1500-1625 1750
1750 2000
1875-2000 2250
2125-2250 2500
2375 2750
2500-2750 3000
2875 3250
3000-3125 3500
*These total daily doses of DEPAKOTE cannot be directly converted to an 8 to 20% higher total daily dose of DEPAKOTE ER because the required dosing strengths of DEPAKOTE ER are not available. Consideration may be given at the clinician's discretion to increase the patient's DEPAKOTE total daily dose to the next higher dosage before converting to the appropriate total daily dose of DEPAKOTE ER.
 
zonisamide Zonegran ®

(Chemical class: sulfonamide).  		 Indications: adjunctive therapy for the treatment of partial seizures in adults.  
Initial dose: 100 mg once daily.  After two weeks, the dose may be increased to 200 mg/day for at least two weeks. It can be increased to 300 mg/day and 400 mg/day, with the dose stable for at least two weeks to achieve steady state at each level. Evidence from controlled trials suggests that doses of 100-600 mg/day are effective, but there is no suggestion of increasing response above 400 mg/day. Doses above 100mg may be administered once or twice daily.  
[Supplied:25, 50, 100 mg capsule]

Disclaimer
The authors make no claims of the accuracy of the information contained herein; and these suggested doses are not a substitute for clinical judgement. Neither GlobalRPh Inc. nor any other party involved in the preparation of this program shall be liable for any special, consequential, or exemplary damages resulting in whole or part from any user's use of or reliance upon this material.PLEASE READ THE DISCLAIMER CAREFULLY BEFORE ACCESSING OR USING THIS SITE. BY ACCESSING OR USING THIS SITE, YOU AGREE TO BE BOUND BY THE TERMS AND CONDITIONS SET FORTH IN THE DISCLAIMER.   Read the disclaimer

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