Anticonvulsant levels and reloading: Difference between revisions
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==Reloading== | ==Reloading== | ||
'''Dose (mg) = ideal body weight (kg) X Vd X [desired level - current level (mcg/mL)]''' | '''Dose (mg) = ideal body weight (kg) X Vd X [desired level - current level (mcg/mL)]''' | ||
Revision as of 14:06, 25 August 2015
Background
- IV load can be performed with phenobarbital, phenytoin, valproate, levetiracetam
- Oral loading can be spread over day or more to avoid GI upset
- May use IV vs PO reload at physican discretion[1]
Initial Loading[1]
Anticonvulsant (brand name) | PO Loading Dose | IV Loading Dose |
Carbamazepine (Tegretol) | 8 mg/kg suspension in single oral load | NA |
Gabapentin (Neurontin) | 900 mg/day oral (300 mg tid) for 3 days | NA |
Lamotrigine (Lamictal) | 6.5 mg/kg single oral load if on lamotrigine for >6 mo without a history of rash or intolerance in the past and only off lamotrigine for <5 days | NA |
Levetiracetam (Keppra) | 1,500 mg oral load | Up to 60 mg/kg (rapid loading) |
Phenytoin (Dilantin) | 20 mg/kg divided in maximum doses of 400 mg every 2 hours | 18 mg/kg (max rate of 50 mg/min) |
Fosphenytoin (Cerebyx) | NA | 18 PE/kg IV (max rate of 150 PE/min) |
Valproate (Depacon) | NA | Up to 30 mg/kg IV (max rate of 10 mg/kg/min) |
Reloading
Dose (mg) = ideal body weight (kg) X Vd X [desired level - current level (mcg/mL)]
Volume of Distribution
Agent | Volume of Distribution | Desired Level |
Phenytoin (dilantin) | 0.8 | 20 mcg/mL |
Carbamazepine (tegretol) | 0.8 | 12 mcg/mL |
Phenobarbital | 0.6 | 40 mcg/mL |
Valproate (depakote) | 0.2 | 100 mcg/mL |