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Idrees U, Londner M. Pharmacotherapy Overview of Seizure Management in the Adult Emergency Department. J Pharm Pract 2016. [DOI: 10.1177/0897190005280050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Seizures are a common cause of emergency department visits, and approximately 28% of epilepsy patients present to an emergency department annually for treatment. This article will provide an overview of the pharmacotherapeutic management of seizures and anticonvulsant therapy for patients who present to the adult emergency department, including practical information for pharmacists covering or cross-covering this practice area. The benzodiazepines are reviewed as a class, including dosing strategies, pharmacodynamic considerations, and advantages and disadvantages of lorazepam, diazepam, and midazolam. Indications for the use of phenytoin and fosphenytoin will be reviewed, as well as dosing, adverse effects, and cost-effectiveness data. In addition, dosing, administration, pharmacokinetics, and adverse effects of phenobarbital, carbamazepine, and valproate will be discussed. Clinical indications for serum anticonvulsant concentration monitoring and subsequent calculation of loading doses from serum concentrations are reviewed. Since status epilepticus is a life-threatening emergency, its therapeutic management is reviewed, including the use of continuous infusion midazolam, pentobarbital, and propofol. There are many opportunities for clinical pharmacists to collaborate with other members of the health care team to optimize efficacy and minimize adverse effects of anticonvulsant agents in the emergency department setting.
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Affiliation(s)
- Umbreen Idrees
- Departments of Pharmacy Services and Emergency Medicine, The Johns Hopkins Hospital, Baltimore, Maryland,
| | - Michael Londner
- Department of Emergency Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland
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Abstract
Therapeutic drug monitoring is widely used in the anticonvulsant treatment of persons with epilepsy. Most monitoring uses serum, but many anticonvulsant drugs can as easily be monitored using saliva, including phenobarbital, phenytoin, carbamazepine, lamotrigine, oxcarbazepine, topiramate, levetiracetam, and gabapentin. For highly protein-bound medications such as phenobarbital, phenytoin, and carbamazepine, saliva has the advantage of providing an approximation of the serum free level, the free level presumably being the active moiety. Salivary therapeutic drug monitoring offers a number of advantages over serum therapeutic drug monitoring, including lack of pain, lower cost, and wide potential acceptability by patients and physicians. It has the potential to open new approaches to treatment with strategic at-home monitoring at the time a seizure or adverse event occurs and to allow the collection of cohort-based, pharmacokinetic, and pharmcodynamic data for populations of persons of varying ages and with different medical conditions who require anticonvulsant medications.
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Affiliation(s)
- Robert J. Baumann
- Department of Neurology, Kentucky Clinic, College of Medicine, University of Kentucky, Lexington, Kentucky, baumann @uky.edu
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Stepanova D, Beran RG. Measurement of levetiracetam drug levels to assist with seizure control and monitoring of drug interactions with other anti-epileptic medications (AEMs). Seizure 2014; 23:371-6. [PMID: 24630809 DOI: 10.1016/j.seizure.2014.02.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 01/31/2014] [Accepted: 02/10/2014] [Indexed: 02/08/2023] Open
Abstract
PURPOSE Levetiracetam (LEV) therapeutic range (20-40mg/L) and potential drug interactions were assessed in people with epilepsy (PWE). METHOD Fifty-two PWE had LEV and concomitant medications [carbamazepine (CBZ); valproate (VPA); lamotrigine (LTG)] blood levels measured and compared to seizure activity. Lacosamide (LCM) levels were unavailable. Adopted therapeutic ranges were: 20-40mg/L - LEV; 25-50μmol/L - total CBZ; 6-13μmol/L - free CBZ; 300-750μmol/L - total VPA; 30-75μmol/L - free VPA; and 40-60μmol/L - LTG. Seizure-freedom was assessed and patients followed for almost two years. RESULTS 23 of 52 PWE (44%) used LEV monotherapy and 16/23 (70%) had 'therapeutic' LEV with 13/16 (81%) seizure-free. 29 of 52 (56%) used polytherapy and 16/29 (55%) had 'therapeutic' LEV with 7/16 (44%) seizure-free. 11 of 29 (38%) used CBZ: 4/11 (36%) had therapeutic mean LEV levels and 7/11 (64%) were seizure-free. Fourteen (48%) used VPA: 9/14 (64%) had therapeutic mean LEV levels and 8/14 (57%) were seizure-free. 13 of 29 (45%) used LTG: 8/13 (62%) had therapeutic mean LEV levels and 5/13 (38%) were seizure-free. LEV did not alter CBZ, but CBZ affected LEV. LEV elevated VPA free levels but not VPA total levels. Dosage/concentration was lowered with polytherapy. CONCLUSION LEV range (20-40mg/L) assisted epilepsy management and anti-epileptic medication interactions were suggested with polytherapy thus possibly explaining the impaired efficacy of LEV with polytherapy.
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Affiliation(s)
- Daria Stepanova
- Strategic Health Evaluators, Sydney, New South Wales, Australia
| | - Roy G Beran
- Strategic Health Evaluators, Sydney, New South Wales, Australia; Griffith University, Gold Coast and Brisbane, Queensland, Australia; University of New South Wales, Sydney, New South Wales, Australia.
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Mbuba CK, Ngugi AK, Fegan G, Ibinda F, Muchohi SN, Nyundo C, Odhiambo R, Edwards T, Odermatt P, Carter JA, Newton CR. Risk factors associated with the epilepsy treatment gap in Kilifi, Kenya: a cross-sectional study. Lancet Neurol 2012; 11:688-96. [PMID: 22770914 PMCID: PMC3404220 DOI: 10.1016/s1474-4422(12)70155-2] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Background Many people with epilepsy in low-income countries do not receive appropriate biomedical treatment. This epilepsy treatment gap might be caused by patients not seeking biomedical treatment or not adhering to prescribed antiepileptic drugs (AEDs). We measured the prevalence of and investigated risk factors for the epilepsy treatment gap in rural Kenya. Methods All people with active convulsive epilepsy identified during a cross-sectional survey of 232 176 people in Kilifi were approached. The epilepsy treatment gap was defined as the percentage of people with active epilepsy who had not accessed biomedical services or who were not on treatment or were on inadequate treatment. Information about risk factors was obtained through a questionnaire-based interview of sociodemographic characteristics, socioeconomic status, access to health facilities, seizures, stigma, and beliefs and attitudes about epilepsy. The factors associated with people not seeking biomedical treatment and not adhering to AEDs were investigated separately, adjusted for age. Findings 673 people with epilepsy were interviewed, of whom 499 (74%) reported seeking treatment from a health facility. Blood samples were taken from 502 (75%) people, of whom 132 (26%) reported taking AEDs, but 189 (38%) had AEDs detectable in the blood. The sensitivity and specificity of self-reported adherence compared with AEDs detected in blood were 38·1% (95% CI 31·1–45·4) and 80·8% (76·0–85·0). The epilepsy treatment gap was 62·4% (58·1–66·6). In multivariable analysis, failure to seek biomedical treatment was associated with a patient holding traditional animistic religious beliefs (adjusted odds ratio 1·85, 95% CI 1·11–2·71), reporting negative attitudes about biomedical treatment (0·86, 0·78–0·95), living more than 30 km from health facilities (3·89, 1·77–8·51), paying for AEDs (2·99, 1·82–4·92), having learning difficulties (2·30, 1·29–4·11), having had epilepsy for longer than 10 years (4·60, 2·07–10·23), and having focal seizures (2·28, 1·50–3·47). Reduced adherence was associated with negative attitudes about epilepsy (1·10, 1·03–1·18) and taking of AEDs for longer than 5 years (3·78, 1·79–7·98). Interpretation The sensitivity and specificity of self-reported adherence is poor, but on the basis of AED detection in blood almost two-thirds of patients with epilepsy were not on treatment. Education about epilepsy and making AEDs freely available in health facilities near people with epilepsy should be investigated as potential ways to reduce the epilepsy treatment gap. Funding Wellcome Trust.
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Affiliation(s)
- Caroline K Mbuba
- KEMRI/Wellcome Trust Research Programme, Centre for Geographic Medicine Research (Coast), Kilifi, Kenya
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Cortical hyperexcitability and epileptogenesis: Understanding the mechanisms of epilepsy – Part 1. J Clin Neurosci 2009; 16:355-65. [DOI: 10.1016/j.jocn.2008.08.026] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Accepted: 08/12/2008] [Indexed: 11/22/2022]
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Abstract
Benzodiazepines (BZDs) remain important agents in the management of epilepsy. They are drugs of first choice for status epilepticus and seizures associated with post-anoxic insult and are also frequently used in the treatment of febrile, acute repetitive and alcohol withdrawal seizures. Clinical advantages of these drugs include rapid onset of action, high efficacy rates and minimal toxicity. Benzodiazepines are used in a variety of clinical situations because they have a broad spectrum of clinical activity and can be administered via several routes. Potential shortcomings of BZDs include tolerance, withdrawal symptoms, adverse events, such as cognitive impairment and sedation, and drug interactions. Benzodiazepines differ in their pharmacologic effects and pharmacokinetic profiles, which dictate how the drugs are used. Among the approximately 35 BZDs available, a select few are used for the management of seizures and epilepsy: clobazam, clonazepam, clorazepate, diazepam, lorazepam and midazolam. Among these BZDs, clorazepate has a unique profile that includes a long half-life of its active metabolite and slow onset of tolerance. Additionally, the pharmacokinetic characteristics of clorazepate (particularly the sustained-release formulation) could theoretically help minimize adverse events. However, larger, controlled studies of clorazepate are needed to further examine its role in the treatment of patients with epilepsy.
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Affiliation(s)
- J Riss
- Center for Orphan Drug Research, Department of Experimental and Clinical Pharmacology, College of Pharmacy, University of Minnesota, Minneapolis, MN, USA
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Inhibition of human aromatase complex (CYP19) by antiepileptic drugs. Toxicol In Vitro 2008; 22:146-53. [DOI: 10.1016/j.tiv.2007.09.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2007] [Revised: 08/21/2007] [Accepted: 09/06/2007] [Indexed: 11/23/2022]
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Antiepileptic drug therapy in pregnancy I: gestation-induced effects on AED pharmacokinetics. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2008; 83:227-40. [PMID: 18929085 DOI: 10.1016/s0074-7742(08)00013-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
The ideal management of women with epilepsy during pregnancy involves achieving an optimal balance between minimizing fetal exposure to the deleterious influences of both antiepileptic drugs (AEDs) and of seizures. Women with increased seizures during pregnancy tend to have subtherapeutic AED concentrations. Multiple physiological changes during pregnancy influence drug disposition, including increased volume of distribution, increased renal elimination, altered hepatic enzyme activity, and a decline in plasma protein concentrations. Many of the AEDs are characterized by significant increases in clearance during pregnancy. Studies performed thus far provide convincing findings for significant increases in the clearance of lamotrigine and phenytoin during pregnancy; other studies support that phenobarbital, oxcarbazepine, and levetiracetam clearances also most likely increase during pregnancy. Therapeutic drug monitoring of lamotrigine with adjustment of dosages during pregnancy to maintain that individual's target concentration has been shown to decrease the risk for increased seizure frequency. Reports of seizure worsening with decreased concentrations of other AEDs have been reported but not studied in similar formal protocols. Future studies of formal pharmacokinetic modeling of AEDs during pregnancy, with assessment of maternal and fetal/newborn consequences, could provide an important step toward achieving effective drug dosing to maintain therapeutic objectives for the mother but at the same time minimize fetal drug exposure.
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Glauser TA, Mitchell WG, Weinstock A, Bebin M, Chen D, Coupez R, Stockis A, Lu ZS. Pharmacokinetics of Levetiracetam in Infants and Young Children with Epilepsy. Epilepsia 2007; 48:1117-22. [PMID: 17442002 DOI: 10.1111/j.1528-1167.2007.01090.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To assess the single-dose pharmacokinetics of levetiracetam and its major metabolite ucb L057 in infants and young children with epilepsy. METHODS Eligible patients with a stable regimen of antiepileptic medications received a single oral dose of levetiracetam 20 mg/kg administered as a 10% oral solution followed by a 24-hour pharmacokinetic evaluation. RESULTS Thirteen subjects (age 2.3-46.2 months) enrolled and received levetiracetam; 12 provided evaluable pharmacokinetic data. Levetiracetam was rapidly absorbed and reached peak plasma concentration (t(max)) 1.4 +/- 0.9 hours after dosing. The mean half-life (t(1/2)) of levetiracetam was 5.3 +/- 1.3 hours, and the apparent clearance was 1.46 +/- 0.42 mL/min/kg. Graphical differences were observed among three age subgroups (1 to <6 months, 6 to <24 months, and 24 to <48 months); however, statistical analysis was limited due to each subgroup's small sample size. No significant gender differences were detected. Treatment-emergent adverse events were seen in three patients (23.1%) but were not considered to be related to levetiracetam. CONCLUSIONS The mean t(1/2) of levetiracetam was shorter and its apparent clearance was more rapid for infants and young children than that previously reported for adults. When determining dosage, age-dependent drug clearance should be considered; these findings suggest that a larger dose of levetiracetam (corrected for body weight) needs to be considered for infants and young children with epilepsy than that given to adults with epilepsy. A single dose of levetiracetam was well tolerated in this study population.
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Affiliation(s)
- Tracy A Glauser
- Children's Hospital Medical Center, Department of Neurology, Cincinnati, Ohio 45229, USA.
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Abstract
OBJECTIVE To review and evaluate the medical literature concerning antiepileptic drug (AED) therapy in elderly patients. DATA SOURCES A MEDLINE search (1982-December 2004) was conducted. Bibliographies of the articles identified were also reviewed, and an Internet search engine was used to identify additional pertinent references. STUDY SELECTION AND DATA EXTRACTION Clinical studies and reviews were evaluated, and relevant information was included. DATA SYNTHESIS The elderly have the highest incidence of seizures among all age groups. Complex partial seizures are the most common, followed by primary generalized tonic-clonic seizures. An accurate diagnosis may prove difficult because of a low suspicion of epilepsy in the elderly and other diseases that may mimic seizures. Most AEDs are approved for treatment of elderly patients who have partial and tonic-clonic seizures. However, a number of age-related variables should be addressed when selecting an appropriate AED. Age-dependent differences in pharmacokinetics and pharmacodynamics of AEDs must be taken into account. Drug-drug interactions must be considered since elderly people often take multiple medications. The ultimate factor that often determines AED selection is tolerability. CONCLUSIONS Numerous factors must be considered in treating elderly patients for seizures, but maximizing the ability of patients to tolerate drug therapy is often the basis for AED selection. Special consideration should be made along several lines, including elderly patients' cognitive functioning and their tendency to respond to lower AED concentrations.
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Affiliation(s)
- William R Garnett
- Medical College of Virginia, Virginia Commonwealth University, PO Box 980533, Richmond, VA 23298-0533, USA.
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ten Berg K, Samrén EB, van Oppen AC, Engelsman M, Lindhout D. Levetiracetam use and pregnancy outcome. Reprod Toxicol 2005; 20:175-8. [PMID: 15808801 DOI: 10.1016/j.reprotox.2004.12.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2004] [Revised: 11/23/2004] [Accepted: 12/04/2004] [Indexed: 11/26/2022]
Abstract
Prenatal exposure to levetiracetam (LEV) has been shown to cause skeletal abnormalities and growth retardation in animal studies, but the teratogenicity of this new antiepileptic drug in humans is still unknown. We detected no malformations in a series of 11 pregnancies with LEV exposure, although it was striking that three cases had a low birth weight. There may be an association between maternal LEV use and reduced birth weight, but too few cases have been monitored so far. We recommend that the outcomes of all pregnancies exposed to LEV should be carefully registered.
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Affiliation(s)
- Klara ten Berg
- Department of Medical Genetics, University Medical Centre Utrecht, PO Box 85090, 3508 AB Utrecht, The Netherlands.
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Sukumaran S, Herbert J, Tracey J, Delanty N. Safety of newer generation anti-epileptic drugs in non-accidental overdose: an Irish population study. Seizure 2005; 14:151-6. [PMID: 15797348 DOI: 10.1016/j.seizure.2004.02.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
UNLABELLED Seven new anti-epileptic drugs (AEDs) have become available in Ireland over the last 10 years; data from animal models and clinical trials suggest that they have a superior safety profile to older AEDs. A specific relationship between epilepsy and psychiatric co-morbidity has long been recognised, including the relationship between epilepsy and suicide. AEDs are common agents taken in intentional drug overdoses. We undertook a study to review the frequency and outcome of non-accidental overdose with seven new AEDS in an Irish population from 1996 to 2000. METHOD All reported cases of drug overdoses with AEDs from 1996 to 2000 were reviewed. Data was provided by the National Poisons Information Centre, Beaumont Hospital and the Central Statistics Office. Medical records from Beaumont Hospital were reviewed in specific cases of serious drug toxicities. An extensive review of published literature reviewing the safety profile of these AEDs was performed and medical literature retrieved from the databases of the pharmaceutical industry was similarly reviewed. RESULTS Of the 164 reported cases of newer AEDs, there were no fatalities among the cases followed up. CONCLUSION The absence of mortalities and serious consequences from deliberate self-poisoning with the newer agents is supportive evidence for the superior safety profile of the newer AEDs.
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Affiliation(s)
- S Sukumaran
- Department of Neurology, Beaumont Hospital, Beaumont Road, Dublin 9, Ireland
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Ondo WG, Jimenez JE, Vuong KD, Jankovic J. An Open-Label Pilot Study of Levetiracetam for Essential Tremor. Clin Neuropharmacol 2004; 27:274-7. [PMID: 15613931 DOI: 10.1097/00002826-200411000-00004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The objective of this study was to determine whether levetiracetam warrants further investigation as a treatment of essential tremor (ET). The authors conducted a 4 -week, open label trial of levetiracetam (Keppra, UCB Pharmaceuticals) in 10 patients diagnosed with ET. Patients were assessed with the complete Tremor Rating Scale (TRS), global impression measures, and adverse events at baseline, after 2 weeks low-dose 500 mg bid and at 4 weeks high-dose 1500 mg bid. All 10 subjects (mean age, 68.6 +/- 7.4 years; seven men, 9 with a positive family history of ET) completed the trial. The TRS observed tremor section modestly improved in 8 subjects (P <0.01). The TRS writing section, water pouring section, and activities of daily living section did not change, and visual analog scores did not change. Subjects rated themselves as "much improved" (n=3), moderately improved (n=1), unchanged (n=1), and mildly worse (n=5). Adverse events included dizziness (n=2), sedation (n=1), and nervousness (n=1). Levetiracetam was well tolerated but failed to improve tremor consistently in this small trial.
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Affiliation(s)
- William G Ondo
- Baylor College of Medicine, Department of Neurology, Houston, Texas 77030, USA.
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Abstract
Pregabalin is a potent ligand for the alpha-2-delta subunit of voltage-gated calcium channels in the central nervous system that exhibits potent anticonvulsant, analgesic, and anxiolytic activity in a range of animal models. In addition, pregabalin has been shown to be a highly effective adjunctive therapy for partial seizures in clinical trials. Potent binding to the alpha-2-delta site reduces depolarization-induced calcium influx with a consequential modulation in excitatory neurotransmitter release. Pregabalin has no demonstrated effects on GABAergic mechanisms. Pregabalin demonstrates highly predictable and linear pharmacokinetics, a profile that makes it easy to use in clinical practice. Absorption is extensive, rapid, and proportional to dose. Time to maximal plasma concentration is approximately 1 h and steady state is achieved within 24-48 h. These characteristics reflect the observed onset of efficacy as early as day two in clinical trials. High bioavailability, a mean elimination half life (t(1/2)) of 6.3 h, and dose-proportional maximal plasma concentrations and total exposures predict a dose-response relationship in clinical practice and allow an effective starting dose of 150 mg/day in clinical practice without need for titration. Administration with food has no clinically relevant effect on the amount of pregabalin absorbed, providing for a dosing regimen uncomplicated by meals. Pregabalin does not bind to plasma proteins and is excreted virtually unchanged (<2% metabolism) by the kidneys. It is not subject to hepatic metabolism and does not induce or inhibit liver enzymes such as the cytochrome P450 system. Therefore, pregabalin is unlikely to cause, or be subject to, pharmacokinetic drug-drug interactions--an expectation that has been confirmed in clinical pharmacokinetic studies. However, dose adjustment may be necessary in patients with renal insufficiency. Thus, the pharmacological and pharmacokinetic profiles of pregabalin provide a predictable basis for its use in clinical practice.
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Affiliation(s)
- Elinor Ben-Menachem
- Department of Clinical Neuroscience, Sahlgrenska Academy, Göteborg University, Göteborg, Sweden.
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Abstract
For the successful treatment of epilepsy, accurate diagnosis of epilepsy and epileptic seizures, and proper selection of antiepileptic drugs (AED) according to the classification of epileptic syndromes are fundamentally important. Efficacy of AED treatment, however, depends not only on its pharmacological action but also on its efficient use, namely a rationally thinking tailor-made treatment considering the characteristics of each patients, i.e. individual differences in pharmacokinetics, factors influencing AED concentrations, AED interactions, and comprehensively their life style and psychosocial factors.
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Liedtke MD, Lockhart SM, Rathbun RC. Anticonvulsant and antiretroviral interactions. Ann Pharmacother 2004; 38:482-9. [PMID: 14970370 DOI: 10.1345/aph.1d309] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE To evaluate the clinical significance of interactions between anticonvulsant and antiretroviral agents and provide recommendations regarding their concurrent use. DATA SOURCES A PubMed search (1966 to April 2003) was conducted using individual anticonvulsant and antiretroviral drug names and the following key search terms: anticonvulsant, antiepileptic, antiretroviral, protease inhibitor, and pharmacokinetic. Abstracts from scientific meetings that pertained to drug interactions were manually reviewed. STUDY SELECTION AND DATA EXTRACTION All articles identified by the PubMed search were examined. Articles and abstracts from scientific meetings with relevant information were included. DATA SYNTHESIS Six case reports were identified that describe interactions between anticonvulsant agents and protease inhibitors. In several reports, carbamazepine serum concentrations increased by approximately two- to threefold with concurrent ritonavir, resulting in carbamazepine-related toxicity. Carbamazepine was also associated with loss of viral suppression when combined with indinavir. Phenytoin serum concentrations were decreased with nelfinavir in a patient who developed recurrent seizures. The effect of ritonavir on phenytoin was variable; a 30% reduction in phenytoin serum concentration occurred in one patient, while no apparent change was observed in another. Interactions with nonnucleoside reverse-transcriptase inhibitors are poorly characterized because existing data involve concurrent protease inhibitor therapy. The utility of newer anticonvulsant agents is explored. Experience with newer anticonvulsant agents in 2 patients at our site is also described. CONCLUSIONS Limited data exist regarding interactions between anticonvulsant and antiretroviral agents. Valproic acid and newer anticonvulsant agents may provide useful alternatives to first-generation agents. Clinicians need to be diligent when monitoring for anticonvulsant-antiretroviral interactions because of the potential for toxicity, loss of seizure control, and incomplete viral suppression.
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Affiliation(s)
- Michelle D Liedtke
- Department of Pharmacy, Clinical and Administrative Sciences, College of Pharmacy, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73117, USA
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Abstract
PURPOSE To evaluate the efficacy of levetiracetam in cases of refractory primary generalised epilepsy. METHODS Three patients with refractory primary generalised epilepsy were treated with levetiracetam monotherapy; one with absence seizures, myoclonic jerks and generalised tonic-clonic (GTC) seizures one with myoclonic jerks and GTC seizures, and one with only GTC seizures. All three patients had generalised spike wave on the EEG and had failed at least three antiepileptic drugs (AEDs) before trying levetiracetam. RESULTS All three patients tolerated levetiracetam well and became seizure free for at least 6 months. Therapeutic doses of levetiracetam ranged from 1250 to 3000 mg/day. CONCLUSION Levetiracetam, a new AED with a novel mechanism(s) of action, should be considered for patients with refractory primary generalised epilepsy.
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Affiliation(s)
- Jeffrey Cohen
- Beth Israel-Singer Division, 170 East End Avenue at 87th Street, New York, NY 10128, USA.
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Abstract
The introduction of these new antiepileptic drugs, from felbamate to levetiracetam, raised hope of control of epilepsy with fewer adverse effects and improved quality of life. Unfortunately, many patients continue to experience refractory epilepsy despite the use of these new agents, and dose-related adverse effects and idiosyncratic reactions continue to be problematic. A recent report describes six new compounds in preclinical development, and five in clinical trials [131]. As the number of available, effective, but imperfect antiepileptic drugs increases, many challenges remain. These include: choosing the drug appropriate for the epileptic syndrome, assessing accurately the range of a drug's adverse effects in an individual patient, and considering carefully the drug's interactions in combination drug therapy. In considering drug combinations, differing mechanisms of drug action and favorable pharmacodynamic interactions (an area requiring additional studies) are of importance. Clinicians caring for children who have epilepsy anticipate further advances in the pharmacogenetics and molecular pathophysiology of epilepsy, leading to individually tailored, effective, and safe therapy.
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Affiliation(s)
- Ann M Bergin
- Division of Epilepsy and Clinical Neurophysiology, Children's Hospital, 300 Longwood Avenue, HU2, Boston, MA 02115, USA.
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Abstract
Severe migraine affects more than 28 million Americans. It is associated with episodic as well as long-term disability and suffering, yet it is underdiagnosed and undertreated. Acute treatments have advanced considerably, ignited by sumatriptan and the subsequent triptans; unfortunately migraine prevention has lagged far behind. There are no great migraine preventives! No migraine preventive agent studied in good randomized, double blind, placebo-controlled trials proved to be 50% better than placebo. Migraine trials typically focus on episodic migraine, a milder, gentler type of migraine that is selected for low frequency, lack of daily headaches, no preventive need, and previous failure to no more than a few preventive agents. These features are not typical of the usual migraine patient seen in most neurologic practices, thus the results of clinical trials may not carryover to real world situations. Treatment of frequent, chronic, or pervasive migraine is inadequate, and never has been studied in randomized controlled trials. Traditional migraine preventives, eg, beta-blockers, calcium channel blockers, and tricyclic antidepressants, are often ineffective in difficult or complicated populations. The antiepileptic drugs represent a category of pharmaceutics that target the neuronal instability and central hyperexcitability of migraine, and, through these actions, may be more effective than traditional preventives. Episodic migraine attacks are associated with peripheral and central sensitization; however, if attacks are frequent, severe, or long lasting, this sensitization may increase the risk of developing daily headaches. If antiepileptic drugs have an effect on central sensitization, perhaps mediated via glutamate inhibition or gamma-aminobutyric acid potentiation, it is appropriate to use these agents early in migraine treatment, particularly in the highly comorbid patient, possibly in conjunction with agents that antagonize the 5HT2 receptor. This report reviews the best currently available evidence on antiepileptic drugs in the prevention of episodic migraine, and tabulates potential drug-drug and cytochrome P450 interactions. All antiepileptic drugs presented are effective in migraine prevention. However, deciding on the best agent for each individual patient will require recognizing comorbidity and assessing antiepileptic drug pharmacodynamics, tolerability, and safety.
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Affiliation(s)
- Steve D. Wheeler
- Ryan Wheeler Headache Treatment Center, 20601 Old Cutler Road, Miami, FL 33189, USA.
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Gibson G. Efficacy of levetiracetam in developmentally disabled patients: a review of the literature and six case reports. Epilepsy Behav 2002; 3:280-284. [PMID: 12662610 DOI: 10.1016/s1525-5050(02)00002-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Objective. Seizures in developmentally disabled are often refractory to treatment. This study aimed to expand the clinical experience with levetiracetam as an antiepileptic drug (AED) for this population.Methods. Four males and two females (aged 25-51) with mental retardation requiring institutionalization and uncontrolled seizures (1.7-12.2/month) received levetiracetam (0.5-2.5g/day) in addition to their standard AEDs. Clinical response was closely followed for 4-10 months (mean, 6 months) with respect to seizure control and adverse effects.Results. Two of the patients became seizure-free, while the other four had seizure reductions ranging from 71 to 92%. None of the patients experienced adverse effects, and three had improvements in behavior.Conclusions. Levetiracetam may be extremely effective in patients with developmental disability. Behavioral abnormalities improved in 50% of the patients.
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Affiliation(s)
- Gordon Gibson
- Baptist Medical Towers I, Suite 900, 9601 Lile Drive, 72205-6370, Little Rock, AR, USA
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