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Abstract
A study was designed to determine if the admixture of phenytoin in normal saline would remain physically stable for a suitable period of time to allow for intravenous infusion. Five phenytoin concentrations (1.0 mg/ml, 2.5 mg/ml, 5.0 mg/ml, 7.5 mg/ml, and 10.0 mg/ml) were prepared in triplicate by adding a sufficient volume of normal saline to the appropriate volume of phenytoin sodium injection to produce a total volume of 100 ml. Aliquots of all solutions were withdrawn at zero, 1, 8, 16, and 24 hours. Solutions were filtered through a 0.22 micron millipore filter and the concentration of phenytoin and pH of each solution was determined. A significant concentration difference was not seen between zero time and 24 hours. The pH of the samples ranged from 9.75 to 11.00. While phenytoin sodium appears to be stable in the concentrations tested when sodium chloride 0.9% is the vehicle, several important factors must be considered and caution must be used if the admixture is administered intravenously.
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Abstract
A retrospective review of the safety, tolerability, and efficacy of vagus nerve stimulation (VNS) in 48 patients with intractable partial epilepsy was performed. Side effects were few and mild to moderate. Mean seizure frequency decreased by 26% after 1 year, 30% after 5 years, and 52% after 12 years with VNS treatment.
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Affiliation(s)
- B M Uthman
- Neurology Service, Malcom Randall Department of Veterans Affairs Medical Center, University of Florida College of Medicine and McKnight Brain Institute, Gainesville 32608, USA.
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Pellock JM, Smith MC, Cloyd JC, Uthman B, Wilder BJ. Extended-release formulations: simplifying strategies in the management of antiepileptic drug therapy. Epilepsy Behav 2004; 5:301-7. [PMID: 15145298 DOI: 10.1016/j.yebeh.2004.01.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2003] [Revised: 01/26/2004] [Accepted: 01/27/2004] [Indexed: 10/26/2022]
Abstract
Advances in our understanding, diagnosis, and treatment of seizure disorders have transformed the management of epilepsy. As the number of antiepileptic drugs and their formulations increase, so do the expectations of therapy. Once limited to attaining complete control of seizures, epilepsy management now strives to enable patients to lead lifestyles consistent with their own capabilities. Extended-release antiepileptic drug formulations can help achieve the primary treatment goals for many patients with epilepsy: preventing occurrence of seizures and preventing or reducing side effects. The dosing flexibility and consistency of serum levels (without marked peak-to-trough fluctuations) conferred by extended-release formulations help achieve these goals. These same attributes of extended-release formulations may also improve compliance, quality of life, and patient satisfaction with treatment.
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Affiliation(s)
- John M Pellock
- Division of Child Neurology, Virginia Commonwealth University, Medical College of Virginia, PO Box 980211 VCU-MCV, Richmond, VA 23298-0211, USA.
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Pellock JM, Wilder BJ. The neurology of special populations. Neurology 2004. [DOI: 10.1212/wnl.62.5_suppl_2.s1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Abstract
PURPOSE Acute pancreatitis has been associated with a number of medications, including valproate (VPA). Valproate-coincident pancreatitis is uncommon and is usually associated with other risk factors; however, the United States Food and Drug Administration has issued a box warning for risk of acute pancreatitis with VPA products. We reviewed cases of pancreatitis in VPA-treated patients from the clinical database of VPA/divalproex trials and compared the incidence of elevated amylase levels between VPA- and placebo-treated patients. METHODS Report rates of acute pancreatitis coincident with VPA use in 34 clinical trials were calculated. Incidence rates of amylase elevations above the normal range in three clinical placebo-controlled migraine trials were compared between VPA- and placebo-treated patients. RESULTS Among 3,007 VPA-treated patients in 34 clinical trials, two reports of pancreatitis were considered by investigators to be probably related to VPA. Both patients recovered. Similar rates of amylase elevations were observed in VPA- (5.9%) and placebo-treated (6.1%) patients in the three migraine headache trials. CONCLUSIONS VPA-coincident acute pancreatitis is uncommon and idiosyncratic. Checking amylase levels in the absence of other clinical signs and symptoms provides little value for predicting pancreatitis. Physicians should be guided by clinical symptoms of pancreatitis to identify cases.
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Affiliation(s)
- John M Pellock
- Virginia Commonwealth University Health Systems/Medical College of Virginia Hospitals, Richmond, Virginia 23298, USA.
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Abstract
The authors examined the effect of food on the bioavailability of Dilantin Kapseals in a nonblinded, single 100-mg dose, randomized, crossover trial. Drug was administered after an 8-hour fast and after a high-fat meal. Differences in mean dietary state values were +6% for maximum concentrations (C(max)) and -2% for area under the curve. Associated 90% CI were within US Food and Drug Administration criteria, confirming the absence of a food effect. Thus, patients may take 100-mg Dilantin Kapseals without regard to meals.
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Affiliation(s)
- J Cook
- Department of Clinical Pharmacokinetics and Pharmacodynamics, Pfizer Global Research and Development, Ann Arbor, MI 48105, USA.
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Wilder BJ, Leppik I, Hietpas TJ, Cloyd JC, Randinitis EJ, Cook J. Effect of food on absorption of Dilantin Kapseals and Mylan extended phenytoin sodium capsules. Neurology 2001; 57:582-9. [PMID: 11524464 DOI: 10.1212/wnl.57.4.582] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Because of phenytoin's narrow therapeutic index and nonlinear pharmacokinetics, food-induced alterations in absorption may markedly influence drug concentrations and, in turn, safety and effectiveness. Potential food-associated differences between 100-mg Mylan (Mylan Pharmaceuticals) extended-release phenytoin sodium capsules and Parke-Davis 100-mg Dilantin Kapseals were examined. METHODS A single-dose, two-way crossover study was conducted in 24 healthy subjects to determine the effect of a high-fat meal on the pharmacokinetics of both formulations. Pharmacokinetic parameters were estimated by noncompartmental methods. The impact of switching products on steady-state phenytoin concentrations was investigated through simulation using pharmacokinetic data previously obtained from 30 epileptic patients. RESULTS Based on AUC(0-infinity), bioavailability of the Mylan product administered with food was 13% lower than that observed with Dilantin Kapseals. Simulations of substituting the Mylan product for Dilantin suggested that the 13% decrease in bioavailability would result in a median 37% decrease (range 19 to 58%) in plasma phenytoin concentrations when the drug is given with food; in 46% of patients, phenytoin concentrations would likely fall below the therapeutic range of 10 to 20 mg/L. Simulations of substituting Dilantin for the Mylan product suggested that the 15% increase in bioavailability would result in a median 102% increase (range 24 to >150%) in plasma phenytoin concentrations, with 84% of patients having phenytoin concentrations above the therapeutic range. CONCLUSIONS Results suggest that when taking phenytoin sodium with food, product switches may result in either side effects or loss of seizure control.
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Affiliation(s)
- B J Wilder
- Department of Neurology and Neuroscience, College of Medicine, University of Florida, Gainesville, 32606, USA.
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Affiliation(s)
- B J Wilder
- Department of Neuroscience and Neurology, University of Florida College of Medicine, Gainesville, Florida, USA
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Wilder BJ. Medical management of epilepsy: consensus report on current clinical practice. Neurology 1998. [DOI: 10.1212/wnl.51.5_suppl_4.s1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Ramsay RE, Wilder BJ, Uthman BM, Garnett WR, Pellock JM, Barkley GL, Leppik IE, Knapp LE. Intramuscular fosphenytoin (Cerebyx) in patients requiring a loading dose of phenytoin. Epilepsy Res 1997; 28:181-7. [PMID: 9332883 DOI: 10.1016/s0920-1211(97)00054-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Fosphenytoin (Cerebyx), is a water soluble prodrug that is rapidly and completely converted to phenytoin. This study reports the injection-site tolerance and safety of intramuscular fosphenytoin (> 10 mg/kg doses) in 60 patients requiring a phenytoin loading dose. Patients received injections at single or multiple sites with volumes ranging from 4 to 30 ml per injection site. The majority of patients had no irritation (erythema, swelling, tenderness, bruising) or complaints of discomfort related to fosphenytoin injection either after injection (95%) or at follow-up (88%). Irritation, when reported, was mild in all cases. Forty of 60 patients (67%) reported transient side effects, primarily involving the central nervous system, such as nystagmus, dizziness or ataxia, which are commonly associated with phenytoin therapy. All patients received prescribed doses; no patient had an injection(s) stopped due to intolerance or side effects. No serious adverse events occurred with intramuscular fosphenytoin. In this study, intramuscular fosphenytoin was demonstrated to be a safe and well tolerated, and in many instances, a preferable alternative to other means of phenytoin loading.
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Affiliation(s)
- R E Ramsay
- International Center for Epilepsy, University of Miami, FL 33136, USA
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Wilder BJ, Homan RW. Definition of rational antiepileptic polypharmacy. Epilepsy Res Suppl 1997; 11:253-8. [PMID: 9294743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Rational polypharmacy is in its earliest stages of development and will require substantial additional development to realize its full potential. Indeed, despite the powerful appeal of the concept, clinical proof is not yet available that RP is superior to monotherapy. Important questions need to be addressed: 1. Will RP control seizures more effectively than monotherapy? 2. What data are needed to develop RP for a specific patient? 3. Will RP be cost effective? 4. Can RP be developed which will treat or prevent epilepsy while controlling seizures? Possible approaches to these questions could include: 1. The development of a data base for prospective use to monitor patients being treated at Epilepsy Centers using RP principles. 2. Use the data obtained from the above to construct more specific studies to compare identified combination therapies with monotherapy. 3. Prospectively compare in a placebo controlled, blinded study, the effect of the combination of an anti-ictal medication and a laboratory proven antiepileptic drug for prevention of the development of epilepsy in an at risk population such as head trauma or stroke.
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Affiliation(s)
- B J Wilder
- University of Florida, College of Medicine, Gainesville, USA
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Hurd RW, Wilder BJ, Helveston WR, Uthman BM. Treatment of four siblings with progressive myoclonus epilepsy of the Unverricht-Lundborg type with N-acetylcysteine. Neurology 1996; 47:1264-8. [PMID: 8909441 DOI: 10.1212/wnl.47.5.1264] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The finding of increased activity of the enzyme extracellular superoxide dismutase in four siblings with progressive myoclonus epilepsy of the Unverricht-Lundborg type (PME-UL) prompted the addition of antioxidants to these patients' treatment regimen. After 6 months treatment with vitamin E, selenium, riboflavin, and zinc, there was some improvement in patient awareness and speech. N-acetylcysteine (NAC) is a sulfhydryl antioxidant that increases cellular glutathione and the activity levels of several antioxidant enzymes and has additional actions that contribute to its demonstrated efficacy in preventing or decreasing damage in models of neuronal toxicity. We treated the affected siblings with 4 to 6 grams a day of NAC in addition to the other antioxidants and magnesium. There has been a marked decrease in myoclonus and some normalization of somatosensory evoked potentials with NAC treatment. The patients were treated with NAC for up to 30 months with continued beneficial effects. NAC may prevent further deterioration in the clinical course of patients with PME-UL and may be indicated in other neurodegenerative conditions where excess free radical activity may contribute to disease progression.
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Affiliation(s)
- R W Hurd
- Neurology Service, Gainesville Veterans Affairs Medical Center, FL
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Abstract
In the last few years a number of new antiepileptic drugs have been introduced for the treatment of epilepsy. In addition to the standard antiepileptic drugs, clobazam, vigabatrin, gabapentin, and lamotrigine have been introduced. The choice of the best antiepileptic drug for an individual patient has become more complex. In this review the clinical benefits of the standard and the new antiepileptic drugs are presented.
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Affiliation(s)
- B J Wilder
- University of Florida College of Medicine, Gainesville, USA
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Wilder BJ, Campbell K, Ramsay RE, Garnett WR, Pellock JM, Henkin SA, Kugler AR. Safety and tolerance of multiple doses of intramuscular fosphenytoin substituted for oral phenytoin in epilepsy or neurosurgery. Arch Neurol 1996; 53:764-8. [PMID: 8759983 DOI: 10.1001/archneur.1996.00550080082016] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Safety, tolerability, and pharmacokinetics of fosphenytoin sodium, a water-soluble phenytoin prodrug, were investigated after a temporary substitution of intramuscular fosphenytoin for oral phenytoin sodium in 240 epileptic or neurosurgical patients taking oral phenytoin sodium (100-500 mg/d). METHODS Patients were randomly assigned to 1 of 2 parallel groups. During screening and follow-up, patients were maintained on a regimen of oral phenytoin at an individualized dose. During treatment, the phenytoin-treated patients received intramuscular placebo and their prescribed dose of oral phenytoin; the fosphenytoin-treated patients received oral placebo and intramuscular fosphenytoin equimolar to their phenytoin dose. RESULTS Both groups had similar types and frequencies of mild to moderate adverse events. Fosphenytoin was as well tolerated as intramuscular placebo at the injection site. Intramuscular fosphenytoin equimolar to a patient's oral phenytoin dose produced equal or greater plasma phenytoin concentrations. CONCLUSIONS Dosing adjustments are not required when intramuscular fosphenytoin is temporarily substituted or oral phenytoin therapy is resumed. Intramuscular fosphenytoin is a safe and well-tolerated alternative to oral phenytoin when oral administration is not feasible.
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Affiliation(s)
- B J Wilder
- Department of Neurology, Veterans Affairs Medical Center, Gainesville, Fla, USA
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Affiliation(s)
- B J Wilder
- Department of Neurology, University of Florida College of Medicine, Gainesville, USA
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Faught E, Wilder BJ, Ramsay RE, Reife RA, Kramer LD, Pledger GW, Karim RM. Topiramate placebo-controlled dose-ranging trial in refractory partial epilepsy using 200-, 400-, and 600-mg daily dosages. Topiramate YD Study Group. Neurology 1996; 46:1684-90. [PMID: 8649570 DOI: 10.1212/wnl.46.6.1684] [Citation(s) in RCA: 259] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
We conducted a randomized double-blind comparison of three doses of the novel antiepileptic drug (AED) topiramate (200, 400, and 600 mg/day) and placebo as adjunctive therapy in patients with refractory partial onset epilepsy receiving one or two other AEDs at therapeutic concentrations. A total of 181 patients completed the 12-week baseline phase and were randomized to double-blind therapy. Median percent reductions from baseline in average monthly seizure rate, the principal efficacy evaluation, were 13% for placebo, 30% for topiramate 200 mg/day, 48% for topiramate 400 mg/day, and 45% for topiramate 600 mg/day. For the seizure rate comparison of active drug to placebo p values were: topiramate 200 mg/day, p = 0.051; topiramate 400 mg/day, p = 0.007; topiramate 600 mg/day, p < 0.001. Percent responders ( > or = 50% reduction in seizure rates) were 18% for placebo, 27% for topiramate 200 mg/day, 47% for topiramate 400 mg/day (p = 0.013), and 46% for topiramate 600 mg/day (p = 0.027). A significant (p = 0.003) reduction in secondarily generalized seizures compared with placebo treatment was also documented with topiramate. Topiramate plasma concentrations were closely related to dosage, and there were no significant interactions between topiramate and other AEDs. The minimal effective dose of topiramate in this study population was approximately 200 mg/day. Mild or moderate CNS symptoms were the primary treatment-emergent adverse events, but treatment-limiting adverse events occurred in only 9% of patients given topiramate compared with 7% given placebo. Results of this initial well-controlled study in patients indicate that topiramate is a very promising new AED.
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Affiliation(s)
- E Faught
- Department of Neurology, University of Alabama School of Medicine, Birmingham 35294-0021, USA
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Abstract
Phenobarbital, diazepam, lorazepam, and phenytoin are all currently used for the treatment of acute seizures, including status epilepticus. None of these drugs is considered ideal. Fosphenytoin is a new phenytoin prodrug that fulfills many of the properties of an ideal anticonvulsant drug. The safety, tolerance, and pharmacokinetics of intramuscularly administered fosphenytoin have been evaluated in three clinical trials involving patients requiring loading or maintenance doses of phenytoin. These investigations demonstrated that fosphenytoin is rapidly and completely absorbed after injection into muscle and is quickly converted to produce therapeutic phenytoin plasma concentrations within 30 min of administration. Plasma concentrations of phenytoin achieved with i.m. fosphenytoin exceeded those associated with an equimolar dose of oral phenytoin. i.m. fosphenytoin was well tolerated both locally and systemically. Only mild and transient reactions occurred at the injection site. The most common systemic adverse events reported--somnolence, nystagmus, dizziness, and ataxia--are side effects commonly seen with phenytoin and tended to be mild. Preexisting seizure disorders remained stable. Combination treatment with i.v. diazepam or lorazepam to attain rapid seizure control and i.m. fosphenytoin to maintain the anticonvulsant effect theoretically offers many advantages for control of acute seizures and should be studied.
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Affiliation(s)
- B M Uthman
- Neurology Service, Department of Veterans Affairs Medical Center, Gainesville, FL 32608, USA
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Abstract
We report a patient with Friedreich's disease (FD) who exhibited abnormalities of antioxidant metabolism, including decreased levels of glutathione peroxidase, glutathione reductase, and selenium, and an increased lipid peroxide index. These abnormalities became normal after treatment with N-acetylcysteine, selenium, and low-dose vitamin E therapy. Treatment was associated with a decreased rate of clinical decline. FD is a neurodegenerative disorder that may be related to disturbed antioxidant metabolism; the disorder may be treatable with antioxidant compounds.
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Affiliation(s)
- W Helveston
- Department of Neurology, University of Florida, Gainesville, USA
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Helveston W, Hurd R, Uthman B, Wilder BJ. Abnormalities of glutathione peroxidase and glutathione reductase in four patients with Friedreich's disease. Mov Disord 1996; 11:106-7. [PMID: 8771081 DOI: 10.1002/mds.870110124] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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Devinsky O, Faught RE, Wilder BJ, Kanner AM, Kamin M, Kramer LD, Rosenberg A. Efficacy of felbamate monotherapy in patients undergoing presurgical evaluation of partial seizures. Epilepsy Res 1995; 20:241-6. [PMID: 7796796 DOI: 10.1016/0920-1211(94)00084-a] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The efficacy and safety of felbamate monotherapy were evaluated in 52 patients with refractory partial seizures with or without secondary generalization in a double-blind, randomized, placebo-controlled trial. Each patient completed a routine evaluation for epilepsy surgery and was randomized to receive either felbamate, titrated to a maximum daily dose of 3600 mg over 2 days, or placebo during the 10-day, inpatient, treatment phase. An intent-to-treat analysis was performed on the data of all 52 patients who received study medication, while a separate efficacy analysis also was performed on the data of 43 evaluable patients, which excluded protocol violators. The endpoint of the trial was completing 10 days of treatment or the occurrence of a fourth seizure. The primary efficacy variable was the average daily seizure frequency during the treatment phase for each patient. For the intent-to-treat analysis based on all 52 patients who received study medications, the mean rank of the daily seizure frequency for patients treated with felbamate was 21.6 compared to 29.6 for patients treated with placebo (P = 0.065). In the analysis based on the 43 evaluable patients, the mean rank of the daily seizure frequency for felbamate-treated patients was 17.0 compared to 25.4 for placebo-treated patients. This difference was statistically significant (P = 0.032) in favor of felbamate. Seizure frequency was decreased by 89.5% compared to baseline in nine patients who completed 10 days of felbamate therapy. This study permitted the rapid determination of the anticonvulsant activity of felbamate and demonstrated that felbamate is effective as monotherapy for the treatment of partial seizures.
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Affiliation(s)
- O Devinsky
- NYU School of Medicine, Hospital for Joint Diseases, New York 10003, USA
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Wilder BJ. The treatment of epilepsy: an overview of clinical practices. Neurology 1995; 45:S7-11. [PMID: 7898746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
About 30% of patients with epilepsy remain refractory to medical management despite optimal use of conventional antiepileptic drugs. Seizure control for many patients is often achieved at the expense of adverse drug effects. The need for new drugs is obvious. After 15 years, three new antiepileptic drugs are now clinically available: felbamate, gabapentin, and lamotrigine. These drugs have undergone double-blind, controlled clinical trials for efficacy and safety in patients with predominantly simple, complex partial, and generalized tonic-clonic seizures. All of these new drugs will be used initially in a polypharmacy regimen.
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Affiliation(s)
- B J Wilder
- Veterans Affairs Medical Center, Gainesville, FL 32608
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Abstract
No new antiepileptic drugs (AEDs) were licensed in the United States from 1978 to 1992. In late 1992, felbamate and gabapentin were recommended for approval, and in early 1993, lamotrigine. In July 1993, felbamate was licensed, and gabapentin and lamotrigine may soon follow. Lamotrigine, vigabatrin and clobazam are in use outside the US. Tiagabine, oxcarbazepine, fosphenytoin, topiramate, vigabatrin and zonisamide are in Phase II clinical testing in the US. All of the new AEDs are effective against partial and tonic-clonic seizures. Few controlled clinical trials have been done in patients with absence and myoclonic seizures. Mechanisms of action of the new drugs have not been clearly defined. The new AEDs will provide an opportunity to improve the care of epileptic patients. Even with optimal management with currently available drugs, some 30% of patients remain refractory to medical management.
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Affiliation(s)
- B J Wilder
- University of Florida College of Medicine, Gainesville 32608-1197
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Ben-Menachem E, Mañon-Espaillat R, Ristanovic R, Wilder BJ, Stefan H, Mirza W, Tarver WB, Wernicke JF. Vagus nerve stimulation for treatment of partial seizures: 1. A controlled study of effect on seizures. First International Vagus Nerve Stimulation Study Group. Epilepsia 1994; 35:616-26. [PMID: 8026408 DOI: 10.1111/j.1528-1157.1994.tb02482.x] [Citation(s) in RCA: 433] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Vagus nerve stimulation (VNS) was shown to reduce seizure frequency in refractory epilepsy patients in two pilot studies. Based on these results, a multicenter, prospectively randomized, parallel, double-blind study of patients with refractory partial seizures was initiated. After a 12-week baseline period, identical vagus nerve stimulators were implanted and patients randomized to either a high or low 14-week VNS treatment paradigm. The primary objective was to demonstrate that high VNS (therapeutic parameters) was more effective in reducing partial seizure frequency than was low VNS (less or noneffective parameters). Patients continued receiving antiepileptic drugs (AEDs) with plasma concentrations held constant throughout the study. We report results of the first 67 patients to exit the 14-week acute phase. After 14 weeks of VNS, 31 patients receiving high VNS experienced a mean seizure frequency percentage reduction of 30.9%, which was statistically significant as compared with the mean seizure frequency percentage reduction of 11.3% in 36 patients receiving low VNS (p = 0.029, t test; p = 0.036, Wilcoxon rank-sum test). In addition to the significant intragroup p-values, mean seizure frequency percentage change reached statistical significance for high VNS (p < 0.001) but not low VNS (p = 0.072) as compared with baseline. Twelve of 31 (38.7%) patients receiving high VNS achieved at least 50% reduction in seizure frequency whereas 7 of 36 (19.4%) patients receiving low VNS experienced at least 50% reduction after 14 weeks. The implant procedure and VNS therapy were well tolerated. Our study confirmed the effectiveness of VNS as treatment for epilepsy patients with refractory partial seizures.
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Radulovic LL, Wilder BJ, Leppik IE, Bockbrader HN, Chang T, Posvar EL, Sedman AJ, Uthman BM, Erdman GR. Lack of interaction of gabapentin with carbamazepine or valproate. Epilepsia 1994; 35:155-61. [PMID: 8112239 DOI: 10.1111/j.1528-1157.1994.tb02926.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Gabapentin (GBP) studies were conducted in patients with epilepsy receiving carbamazepine (CBZ, n = 12) or valproate (VPA, n = 14) monotherapy. The effects of GBP coadministration on steady-state CBZ or VPA concentrations and of these antiepileptic drugs (AEDs) on GBP pharmacokinetics were investigated. GBP (400 mg) was coadministered every 8 h for 3 1/3 days with CBZ or for 5 1/3 days with VPA. GBP was well tolerated. Mean steady-state plasma CBZ/CBZ-10,11-epoxide (CBZ-E) and serum VPA concentrations before, during, and after GBP administration were not significantly different. Mean steady-state GBP pharmacokinetic parameters during CBZ or VPA coadministration were similar to steady-state parameters reported in healthy subjects. Thus, no pharmacokinetic interaction exists between CBZ or VPA and GBP. No dosage adjustment is necessary when GBP and CBZ or VPA are coadministered.
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Affiliation(s)
- L L Radulovic
- Department of Pharmacokinetics/Drug Metabolism and Clinical Pharmacology, Parke-Davis Pharmaceutical Research, Division of Warner-Lambert Company, Ann Arbor, Michigan
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Lehesjoki AE, Eldridge R, Eldridge J, Wilder BJ, de la Chapelle A. Progressive myoclonus epilepsy of Unverricht-Lundborg type: a clinical and molecular genetic study of a family from the United States with four affected sibs. Neurology 1993; 43:2384-6. [PMID: 8232963 DOI: 10.1212/wnl.43.11.2384] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We describe clinical and molecular genetic data on a family from the United States in which four of five sibs are affected with progressive myoclonus epilepsy of Unverricht-Lundborg type. The gene for this disorder (EPM1) has previously been mapped to the distal region of chromosome 21. Molecular genetic results suggest that the disease gene in this family is linked to the same region of chromosome 21. Crossover events in the family help refine the gene localization by placing EPM1 between loci CBS and D21S112.
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Affiliation(s)
- A E Lehesjoki
- Department of Medicine Genetics, University of Helsinki, Finland
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29
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Uthman BM, Wilder BJ, Penry JK, Dean C, Ramsay RE, Reid SA, Hammond EJ, Tarver WB, Wernicke JF. Treatment of epilepsy by stimulation of the vagus nerve. Neurology 1993; 43:1338-45. [PMID: 8327135 DOI: 10.1212/wnl.43.7.1338] [Citation(s) in RCA: 151] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We treated 14 patients with medically refractory partial seizures by stimulation of the vagus nerve in two single-blind pilot studies. Patients received stimulation through an implantable, programmable NeuroCybernetic Prosthesis, consisting of a pulse generator and a lead-electrode assembly. The mean reduction in seizure frequency after 14 to 35 months of vagal stimulation was 46.6%. Of the 14 patients, five (35.7%) had a 50% or greater reduction in seizure frequency. Two patients, one of whom had had 10 to 100 seizures per day before stimulation, have been seizure-free for over 1 year. Adverse events were primarily limited to initial hoarseness and a tingling sensation at the electrode site in the neck when the device was activated. Most patients tolerated the device and stimulation well. There were no permanent adverse events. Some cases of medically refractory partial seizures are improved by vagal stimulation.
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Affiliation(s)
- B M Uthman
- Neurology Service, Veterans Administration Medical Center, Gainesville, FL 32608-1197
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30
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Abstract
Evidence from studies of experimental animals indicates that electrical stimulation of the vagus nerve alters EEGs under certain stimulus parameters. We report EEG effects of electrical stimulation of the vagus nerve in 9 patients with medically intractable seizures as part of a clinical trial of chronic vagal stimulation for control of epilepsy. The mechanism of action of the vagal antiepileptic effect is unknown, and we believed that analysis of electrophysiologic effects of vagal nerve stimulation would help elucidate the brain areas affected. The left vagus nerve in the neck was stimulated with a programmable implanted stimulator. Stimulation at various stimulus frequencies and amplitudes had no noticeable effect on EEG activity whether the patient was under general anesthesia, awake, or asleep, but vagus nerve stimulation may interrupt ongoing ictal EEG activity.
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Affiliation(s)
- E J Hammond
- Neurology Service, Department of Veterans Affairs Medical Center, Gainesville, Florida 32608-1197
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31
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Abstract
Evidence from studies of experimental animals indicates that electrical stimulation of the vagus nerve not only can alter the EEG but evokes activity in specific brain areas. We report effects of electrical stimulation of the vagus nerve in 9 patients with medically intractable seizures as part of a clinical trial of chronic vagal stimulation for control of epilepsy. The left vagus nerve in the neck was stimulated with a programmable implanted stimulator. Effects of stimulus amplitude, duration, and rate were studied. Noncephalic reference recording of the vagus nerve evoked potential showed some unusual properties: a scalp negative component occurred with a latency of 12 ms, very high amplitude (< or = 60 microV), and widespread scalp distribution. Field distribution studies indicated that this potential was myogenic in origin and generated in the region of the stimulating electrodes in the neck area. Chemically induced muscle paralysis confirmed this observation. Bipolar scalp recording showed several small-amplitude topographically distinct potentials occurring in 30 ms. No effect, either acute or chronic, could be detected on pattern-reversal evoked potentials, auditory brainstem evoked potentials, auditory 40-Hz potentials, or cognitive evoked potentials.
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Affiliation(s)
- E J Hammond
- Neurology Service, Department of Veterans Affairs Medical Center, Gainesville, Florida 32608-1197
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Hammond EJ, Ballinger WE, Lu L, Wilder BJ, Uthman BM, Reid SA. Absence of cortical white matter changes in three patients undergoing long-term vigabatrin therapy. Epilepsy Res 1992; 12:261-5. [PMID: 1382973 DOI: 10.1016/0920-1211(92)90080-d] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Chronic administration of the experimental antiepileptic drug vigabatrin (gamma-vinyl GABA) to animals has been shown to cause dose-dependent neuropathological changes characterized by a microvacuolation in specific white matter tracts. This finding has led to some concern as to whether similar pathologic changes might occur in patients taking this medication. Here we report on analysis of tissue specimens taken during neurosurgery from three patients undergoing chronic vigabatrin therapy (4 g/day). The first patient, a 34-year-old woman, had taken vigabatrin for 2 years prior to surgery, the second, a 50-year-old man, had taken the drug for 1 year, and a 34-year-old man had taken the drug for 5.3 years. For comparison, similar specimens were taken from three other patients not taking vigabatrin who were undergoing surgery for intractable epilepsy. Specimens from each subject were prepared in an identical manner and examined with light and electron microscopy. All specimens were examined in a blinded fashion. There was some minor nonspecific myelinic splitting seen in both controls and vigabatrin-treated patients but there was no evidence for any drug-induced lesions similar to that seen in experimental animals.
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Affiliation(s)
- E J Hammond
- Neurology Service, Veterans Affairs Medical Center, Gainesville, FL 32608-1197
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33
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Abstract
An implanted stimulating device chronically stimulated the left cervical vagus nerve in epileptic patients. Cerebrospinal fluid concentrations of free and total gamma-aminobutyric acid, homovanillic acid, 5-hydroxyindoleacetic acid, aspartate, glutamate, asparagine, serine, glutamine, glycine, phosphoethanolamine, taurine, alanine, tyrosine, ethanolamine, valine, phenylalanine, isoleucine, vasoactive intestinal peptide, beta-endorphin, and somatostatin were measured before and after 2 months of chronic stimulation in six patients. Significant increases were seen in homovanillic acid and 5-hydroxyindoleacetic acid in three patients, and significant decreases in aspartate were seen in five patients. These changes were associated with a decrease in seizure frequency.
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Affiliation(s)
- E J Hammond
- Neurology Service, Veterans Affairs Medical Center, Gainesville, FL 32608-1197
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Abstract
Over the past 10 years, knowledge gained about the pharmacokinetic profiles of valproate and carbamazepine has increased the clinical effectiveness of their use. Much of the information has been gained through their use as successful antiepileptic medications. As these agents begin to play an increasing role as mood-stabilizing agents in affective disorders, their pharmacokinetic profiles have afforded the psychiatrist well-tolerated medications, particularly when used alone or in combination with lithium. The discussion of pharmacokinetic properties that follows will help the practicing psychiatrist avoid untoward dose-related side effects, while maximizing the desired therapeutic effects with these agents.
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Affiliation(s)
- B J Wilder
- Department of Neurology, University of Florida College of Medicine, Gainesville
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Abstract
We report the case of an 18-month-old child with infantile spasms and a hypsarrhythmic electroencephalogram (EEG) pattern associated with a porencephalic cyst. Surgical removal of the cyst and its surrounding tissue was performed following failure of medical therapy. Postoperatively, the patient has been free of infantile spasms for 12 months and the EEG has normalized. He has been maintained on the same preoperative antiepileptic medications. This case suggests that surgical treatment is helpful in selected patients with infantile spasms and focal CNS lesions.
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Affiliation(s)
- B M Uthman
- Department of Neurology, VA Medical Center, Gainesville, FL 32608
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36
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Browne TR, Mattson RH, Penry JK, Smith DB, Treiman DM, Wilder BJ, Ben-Menachem E, McBride RG, Sherry KM. Multicenter long-term safety and efficacy study of vigabatrin for refractory complex partial seizures: an update. Neurology 1991; 41:363-4. [PMID: 2006001 DOI: 10.1212/wnl.41.3.363] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We followed 66 patients with refractory complex partial seizures and a favorable initial response to vigabatrin for 5 to 72 (median, 43) months. Thirty-seven patients discontinued vigabatrin for the following reasons: benefit-to-risk evaluation, 8; seizure breakthrough, 6; adverse events, 6; seizure breakthrough and adverse events, 5; moved or lost, 4; no longer eligible for study, 2; non-drug-related death, 2; narcotic abuse, 1; and patient request, three. There were no clinically significant abnormalities in laboratory studies including SMA 12, complete blood count, ECG, EEG, and visual evoked response testing, and no toxicity other than reversible, dose-dependent side effects. Based on this and other long-term data, clinical trials of vigabatrin have resumed in the United States and Canada.
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Affiliation(s)
- T R Browne
- Department of Neurology, Boston University School of Medicine, MA
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37
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Abstract
Chronic intermittent stimulation of the vagus nerve is a new method currently being tested for the treatment of medically intractable complex partial seizures (CPS). We have studied the effects of vagal stimulation in nine patients with CPS for 4-16 months to determine its safety and efficacy. With the patients maintained on constant dosages of antiepileptic drugs, we recorded the electroencephalogram and electrocardiogram, and performed clinical laboratory tests and gastric analysis over a 6-week baseline period. The neurocybernetic prosthesis (NCP) was then implanted and connected to two spiral electrodes wound around the left vagus nerve. After a 4-week placebo period, vagal stimulation was started. Stimulation parameters were increased stepwise at monthly intervals until patients were being stimulated for 30-second periods at 20-50 Hz with 1-2 mA of current at 250-500 microseconds pulses. A second 4-week placebo period was added 3 months after the implantation. Thereafter, vagal stimulation was resumed and self-stimulation with magnetic activation was allowed for a 1-minute period at the onset of an aura. Six patients had a significant reduction in the frequency, intensity, or duration of seizures. All patients tolerated the implantation and stimulation well and none reported pain, discomfort, or important changes in their daily activities, sleep habits, eating, swallowing, or breathing. There were no remarkable changes in blood pressure or heart rate.
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Affiliation(s)
- B J Wilder
- Department of Veterans Affairs Medical Center, Gainesville, Florida
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38
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Nuwer MR, Browne TR, Dodson WE, Dreifuss FE, Engel J, Leppik IE, Mattson RH, Penry J, Treiman DM, Wilder BJ. Generic substitutions for antiepileptic drugs. Neurology 1990; 40:1647-51. [PMID: 2234419 DOI: 10.1212/wnl.40.11.1647] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- M R Nuwer
- Department of Neurology, University of California
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39
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Abstract
Evidence from studies of experimental animals indicates that electrical stimulation of the vagus nerve alters behavioral and electrographic seizure activity. We report on effects of electrical stimulation of the vagus nerve in five patients with medically intractable seizures as part of a clinical trial of chronic vagal stimulation for control of epilepsy. The mechanism of action of the vagal antiepileptic effect is unknown, and it is hoped that analysis of electrophysiological effects of vagal nerve stimulation will help elucidate which brain areas are affected. Stimulation of the left vagus nerve in the neck was accomplished with a programmable implanted stimulator. Effects of stimulus amplitude, duration, and rate were studied. Noncephalic reference recording of the vagus-nerve-evoked potential showed some unusual properties: a scalp negative component occurred with latency of 12 ms, very high amplitude (up to 60 microV), and widespread scalp distribution. Field distribution studies indicate that this potential is generated in the neck, in the region of the stimulating electrodes. Muscle paralysis confirms this observation. Stimulation at various frequencies had no noticeable effect on electroencephalographic (EEG) activity regardless of whether the patient was under general anesthesia, awake, or asleep.
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Affiliation(s)
- E J Hammond
- Neurology Service, Veterans Affairs Medical Center, Gainesville, FL 32608-1197
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40
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Abstract
A clinical trial of chronic intermittent vagal stimulation in five patients suggests that the procedure may be safe and effective as adjunctive treatment of medically intractable seizures of partial onset. Patients tolerated well the implantation of the neurocybernetic prosthesis and the vagal stimulation without serious physiological or lifestyle changes. Stimulation of the vagus nerve either reduced the seizure frequency or decreased the duration or intensity of seizures. Adverse side effects were limited to a tingling sensation in the throat and hoarseness during stimulation. A major complication was mechanical interruption of the wire-electrode circuitry, with consequent cessation of stimulation. The small number of patients and the relatively short follow-up period make this a pilot study, but the results are promising.
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Affiliation(s)
- B M Uthman
- Neurology Service, Department of Veterans Affairs Medical Center, Gainesville, FL 32602-1197
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42
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Leppik IE, Boucher BA, Wilder BJ, Murthy VS, Watridge C, Graves NM, Rangel RJ, Rask CA, Turlapaty P. Pharmacokinetics and safety of a phenytoin prodrug given i.v. or i.m. in patients. Neurology 1990; 40:456-60. [PMID: 2314588 DOI: 10.1212/wnl.40.3_part_1.456] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
ACC-9653, a prodrug of phenytoin synthesized to be water soluble, is converted to phenytoin by phosphatases. In this study, 43 patients received ACC-9653 IV or IM. Side effects were transient and minor. The conversion half-lives of ACC-9653 after intravenous and intramuscular administration averaged 8.4 and 32.7 minutes, respectively. Peak phenytoin concentrations occurred 42 minutes after IV and 151 minutes after IM administration.
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Affiliation(s)
- I E Leppik
- Department of Neurology, University of Minnesota, Minneapolis 55414
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43
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Abstract
The drugs currently used in the emergency management of seizures are chiefly phenytoin, phenobarbital, diazepam, lorazepam, and paraldehyde. The combination of intravenous phenytoin and lorazepam has the advantages of rapid onset of action, sustained efficacy, and freedom from drug interactions. The intermittent oral or rectal administration of diazepam is especially useful for acute home treatment of recurrent seizures. Phenytoin prodrug (ACC-9653), an investigational new drug, is promptly absorbed after intramuscular injection. Unlike phenytoin, it does not require propylene glycol and high alkalinity for solubility and therefore does not produce soft-tissue injury after parenteral administration. It appears to be close to an ideal drug for the emergency management of seizures.
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Affiliation(s)
- B M Uthman
- Neurology Service, Veterans Administration Medical Center, Gainesville, Florida 32602
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44
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Abstract
The currently available phenytoin (PHT) solution has many disadvantages stemming from poor aqueous solubility of PHT. A novel approach to solve the problem has been the synthesis of a phosphate ester of PHT (PHT prodrug ACC-9653). This water-soluble compound is metabolized rapidly into PO4 and PHT. A four center open-label, baseline-controlled study of 43 patients with epilepsy maintained on oral twice-daily PHT monotherapy was performed to evaluate the safety and pharmacokinetic profile of the prodrug. Patients received an i.v. or i.m. dose of ACC-9653 at a dose equivalent to the patients' morning dose of PHT. Intravenous dosages were infused at a rate of 75 mg/min, and i.m. dosages were given as one or two injections. After a period of 6 days, during which patients were again maintained with oral PHT, they were given a dose of ACC-9653 via whichever route they had not yet received. The Tmax of the prodrug averaged 5.7 and 36 min (0.095 and 0.606 h) after i.v. and i.m. administrations, respectively. The elimination half-life of ACC-9653 (conversion from prodrug to PHT) after i.v. and i.m. administration was 8.4 and 32.7 min (0.140 and 0.545 h), respectively, and both were independent of the dose. The plasma clearance of ACC-9653 was not dependent on dose or route of administration and averaged 19.8 +/- 1.16 and 17.8 +/- 0.83 L/h after i.v. and i.m. administrations, respectively. The area under curve ratio of PHT after i.m. and i.v. ACC-9653 was 1.17 +/- 0.13 which was not significantly different from 1.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- I E Leppik
- Department of Neurology, University of Minnesota, Minneapolis
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Browne TR, Mattson RH, Penry JK, Smith DB, Treiman DM, Wilder BJ, Ben-Menachem E, Miketta RM, Sherry KM, Szabo GK. A multicentre study of vigabatrin for drug-resistant epilepsy. Br J Clin Pharmacol 1989; 27 Suppl 1:95S-100S. [PMID: 2667606 PMCID: PMC1379686 DOI: 10.1111/j.1365-2125.1989.tb03468.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
1. Vigabatrin (GVG) was given in a single-blind fashion to 89 patients with complex partial seizures (CPS) refractory to conventional drugs. 2. The median number of CPS per month decreased from 11.0 to 5.0 after addition of GVG, and 51% of patients had a 50% or greater decrease in CPS frequency (P less than 0.001). 3. Side effects (principally drowsiness, ataxia, headache) occurred mainly during the initiation of therapy and decreased during therapy. After 12 weeks on GVG side effects significantly interfered with functioning in only 13% of patients, and the efficacy: toxicity ratio warranted continued administration in 74% of patients. 4. Co-administration of GVG resulted in a mean decrease of 20% in phenytoin serum concentration (P less than 0.001). 5. Sixty-six patients having a favourable response to GVG during the single-blind study have been followed for 6-54 (median 33) months on GVG. Only 17 patients have dropped out of long-term follow-up due to break through seizures and/or side effects. No serious systemic or neurological toxicity has been detected.
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Affiliation(s)
- T R Browne
- Department of Neurology, Veterans Administration Medical Center, Boston, MA 02130
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Collins CS, Bailey LB, Hillier S, Cerda JJ, Wilder BJ. Red blood cell uptake of supplemental folate in patients on anticonvulsant drug therapy. Am J Clin Nutr 1988; 48:1445-50. [PMID: 3202094 DOI: 10.1093/ajcn/48.6.1445] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
A group of epileptics (n = 18) and a control group (n = 10) of subjects aged 21-42 y were given 1-mg supplements of folate daily for 1 mo. Anticonvulsant therapy involved phenytoin alone or in combination with phenobarbital. Serum and red blood cell (RBC) folate levels were determined on days 1, 14, and 28. Mean serum and RBC folate levels were greater (p less than 0.05) for the control subjects compared with the epileptic subjects throughout the study. The percent increase in either serum or RBC folate was not different (p greater than 0.05) between the groups. The percent increase in serum folate when expressed as a percent of RBC folate was greater (p less than 0.05) for those epileptics who initially had deficient blood folate levels (serum folate less than 7 nmol/L; RBC folate less than 317 nmol/L) than those who did not. Deficient epileptics may have had an impaired RBC incorporation of circulating (serum) folate compared with nondeficient epileptics.
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Affiliation(s)
- C S Collins
- Food Science and Human Nutrition Department, University of Florida, Gainesville, FL 32611
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47
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Hammond EJ, Rangel RJ, Wilder BJ. Evoked potential monitoring of vigabatrin patients. Br J Clin Pract Suppl 1988; 61:16-23. [PMID: 3145771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Abstract
Well-controlled prospective studies have shown the benefits of converting treatment for patients with epilepsy from polytherapy to monotherapy. Results of trials with valproate have demonstrated its efficacy as monotherapy in patients with generalized tonic-clonic seizures. Several studies have found no significant differences between valproate and phenytoin and carbamazepine in the treatment of partial seizures. In studies in which patients were diagnosed as having one of the primary generalized epilepsies, the response rate of tonic-clonic seizures to valproate establishes valproate as the drug of choice in the epilepsy syndromes with primary generalized tonic-clonic seizures.
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Affiliation(s)
- B J Wilder
- Veterans Administration Medical Center, Neurology Service, Gainesville, Florida 32602
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Abstract
Carbamazepine and phenytoin are drugs of choice in initial monotherapy for adult partial and secondarily generalized tonic-clonic seizures. These designations reflect the results of the Veterans Administration Epilepsy Cooperative Study Group of 1985. An earlier comparative study of carbamazepine and phenytoin by Ramsay and associates found both drugs equally effective in controlling new-onset seizures. Among the advantages of carbamazepine is that it causes relatively few cognitive and dysmorphic side effects. Its disadvantages are its unavailability in parenteral formulation and its metabolic autoinduction. The latter must be compensated for by planned dosage increases to maintain therapeutic plasma steady-state levels during the first 2 or 3 months of treatment. Carbamazepine is judged a drug of choice in the treatment of these secondarily generalized tonic-clonic seizures, and the drug of choice in children, adolescents, and women susceptible to the dysmorphic side effects associated with other anticonvulsant agents.
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Affiliation(s)
- B J Wilder
- Neurology Service, Veterans Administration Medical Center, Gainesville, FL 32602
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50
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Abstract
The long-standing practice of polypharmacy in treating epilepsy is giving way to use of monotherapy. Monotherapy can improve seizure control as well as reduce the risk of serious idiosyncratic reactions, dose-related side effects, and complex drug interactions. Monotherapy also offers improved compliance and cost-effectiveness. The basis of monotherapy is accurate diagnosis and assessment of the patient's seizure type(s), followed by selection of a single appropriate anticonvulsant drug. Many patients currently treated with multiple anticonvulsants can be successfully converted to monotherapy with a carefully monitored program in which troublesome and redundant drugs are gradually withdrawn from the therapeutic regimen.
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Affiliation(s)
- B J Wilder
- Neurology Service, Veterans Administration Medical Center, Gainesville, Florida 32602
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