levetiracetam and Liver-Diseases

Since 1989, eight new antiepileptic drugs (AEDs) have been licensed for clinical use. Levetiracetam is the latest to be licensed and is used as adjunctive therapy for the treatment of adult patients with partial seizures with or without secondary generalisation that are refractory to other established first-line AEDs. Pharmacokinetic studies of levetiracetam have been conducted in healthy volunteers, in adults, children and elderly patients with epilepsy, and in patients with renal and hepatic impairment. After oral ingestion, levetiracetam is rapidly absorbed, with peak concentration occurring after 1.3 hours, and its bioavailability is >95%. Co-ingestion of food slows the rate but not the extent of absorption. Levetiracetam is not bound to plasma proteins and has a volume of distribution of 0.5-0.7 L/kg. Plasma concentrations increase in proportion to dose over the clinically relevant dose range (500-5000 mg) and there is no evidence of accumulation during multiple administration. Steady-state blood concentrations are achieved within 24-48 hours. The elimination half-life in adult volunteers, adults with epilepsy, children with epilepsy and elderly volunteers is 6-8, 6-8, 5-7 and 10-11 hours, respectively. Approximately 34% of a levetiracetam dose is metabolised and 66% is excreted in urine unmetabolised; however, the metabolism is not hepatic but occurs primarily in blood by hydrolysis. Autoinduction is not a feature. As clearance is renal in nature it is directly dependent on creatinine clearance. Consequently, dosage adjustments are necessary for patients with moderate to severe renal impairment. To date, no clinically relevant pharmacokinetic interactions between AEDs and levetiracetam have been identified. Similarly, levetiracetam does not interact with digoxin, warfarin and the low-dose contraceptive pill; however, adverse pharmacodynamic interactions with carbamazepine and topiramate have been demonstrated. Overall, the pharmacokinetic characteristics of levetiracetam are highly favourable and make its clinical use simple and straightforward.

Topics: Adult; Aged; Anticonvulsants; Chemical Phenomena; Chemistry, Physical; Child; Drug Interactions; Drug Monitoring; Humans; Kidney Diseases; Levetiracetam; Liver Diseases; Piracetam

This review discusses the safety and tolerability of levetiracetam, as presented by the available literature, with attention paid to special populations. In Phase II/III trials, the adverse effects occurring more commonly in the treatment groups versus the placebo group were; somnolence (14.8 versus 8.4%), asthenia (14.7 versus 9.1%), infection (primarily common cold) (13.4 versus 7.5%), and dizziness (8.8 versus 4.1%). Adverse events usually appear within the first month after treatment initiation, are not dose-dependent, are mostly mild-to-moderate, generally resolve without medication withdrawal, and are transient when the medication is stopped. No significant changes in haematology and chemistry profiles or weight occurred. Hypersensitivity reactions were rare and no idiosyncratic event has been reported. Open-label studies have added patient data with other epileptic syndromes and from a wider patient pool, such as children and patients with prior psychiatric history. These studies have supported initial safety findings, but have reported increased behavioural adverse events in children and patients with a history of prior behavioural problems. Levetiracetam is proving to be safe and well-tolerated. So far, it appears to have a favourable safety profile in special populations, such as children, the elderly, and patients with hepatic dysfunction. Preliminary data in pregnancy are promising, but more data are needed on the impact of levetiracetam on the developing fetus and pharmacokinetic alterations caused in pregnancy. Adjustments in dosing are required for decreases in renal clearance.

Topics: Abnormalities, Drug-Induced; Adolescent; Adult; Age Factors; Aged; Animals; Anticonvulsants; Asthenia; Bone Density; Child; Child Behavior Disorders; Clinical Trials as Topic; Disorders of Excessive Somnolence; Dizziness; Drug Evaluation, Preclinical; Epilepsy; Female; Headache; Humans; Infections; Kidney Diseases; Levetiracetam; Liver Diseases; Male; Mental Disorders; Mice; Middle Aged; Patient Acceptance of Health Care; Piracetam; Pregnancy; Pregnancy Complications

A subset of the 27 safety and pharmacokinetic studies of levetiracetam has been conducted in selected special populations: children, the elderly, and people with renal or hepatic impairment. The results of these studies indicate that higher doses need to be used for children (on a per-weight basis), and individuals with renal dysfunction require dosage modifications related to creatinine clearance. Individuals with hepatic impairment do not require modifications from standard doses. Little information is available on the effect of levetiracetam on the developing fetus, so cautious use during pregnancy is recommended until more information is available. Additional studies will refine the recommendations for use of levetiracetam in these special populations.

Topics: Adult; Age Factors; Aged; Anticonvulsants; Child; Comorbidity; Contraceptives, Oral; Drug Approval; Drug Interactions; Epilepsy; Female; Humans; Kidney Failure, Chronic; Levetiracetam; Liver Diseases; Male; Middle Aged; Piracetam; Sex Factors

Levetiracetam is a novel orally active antiepileptic drug with a unique preclinical profile. It has a high therapeutic index and potential antiepileptogenic effects. Results of clinical trials indicate activity in partial-onset and generalized seizures. The pharmacokinetic profile of levetiracetam closely approximates the ideal characteristics expected of an antiepileptic drug, with good bioavailability, rapid achievement of steady-state concentrations, linear and time-invariant kinetics, minimal protein binding, and minimal metabolism. The major metabolic pathway of levetiracetam is not dependent on the hepatic cytochrome P450 system, and levetiracetam does not inhibit or induce hepatic enzymes to produce clinically relevant interactions. Sixty-six percent of an administered levetiracetam dose is eliminated unchanged in urine; 24% is metabolized to an inactive metabolite that is detectable in blood and is also excreted in urine. Total body clearance of levetiracetam is decreased in patients with renal impairment, and doses should be modified according to creatinine clearance values. Levetiracetam is not appreciably protein-bound, nor does it affect the protein binding of other drugs. Thus, because of its minimal protein binding and lack of hepatic metabolism, the risk of drug interactions is very low. Levetiracetam has a wide margin of safety and patient-friendly pharmacokinetics that distinguish it from other currently available antiepileptic drugs. This profile may facilitate the clinical management of patients with epilepsy by providing a safer and less-complicated therapeutic strategy.

Topics: Absorption; Adolescent; Adult; Aged; Anticonvulsants; Child; Cytochrome P-450 Enzyme System; Drug Interactions; Epilepsy; Humans; Kidney Diseases; Levetiracetam; Liver Diseases; Middle Aged; Piracetam; Therapeutic Equivalency

Levetiracetam (LEV) is an anti-epileptic drug approved for use in various populations. The pharmacokinetic (PK) behavior of LEV may be altered in the elderly and patients with renal and hepatic impairment. Thus, dosage adjustment is required. This study was conducted to investigate how the physiologically-based PK (PBPK) model describes the PKs of LEV in adult and elderly populations, as well as to predict the PKs of LEV in patients with renal and hepatic impairment in both populations. The whole-body PBPK models were developed using the reported physicochemical properties of LEV and clinical data. The models were validated using data from clinical studies with different dose ranges and different routes and intervals of administration. The fit performance of the models was assessed by comparing predicted and observed blood concentration data and PK parameters. It is recommended that the doses be reduced to ~70%, 60%, and 45% of the adult dose for the mild, moderate, and severe renal impairment populations and ~95%, 80%, and 57% of the adult dose for the Child Pugh-A (CP-A), Child Pugh-B (CP-B), and Child Pugh-C (CP-C) hepatic impairment populations, respectively. No dose adjustment is required for the healthy elderly population, but dose reduction is required for the elderly with organ dysfunction accordingly, on a scale similar to that of adults. A PBPK model of LEV was successfully developed to optimize dosing regimens for special populations.

Topics: Adult; Aged; Humans; Kidney; Levetiracetam; Liver Diseases; Models, Biological; Renal Insufficiency

The aim of this study was to evaluate the risk factors, clinical implications, and prognosis of new-onset seizures that occurred after pediatric liver transplantation, and to assess the efficacy of levetiracetam treatment. The clinical and laboratory data of liver transplanted 28 children who had seizures after liver transplantation and specifically of 18 children who received levetiracetam were analyzed retrospectively. Sixteen patients (88.9%) remained seizure-free and in 2 (11.1%), more than 50% reduction in seizures were detected with levetiracetam treatment. In conclusion, seizures are generally the most common complication by a spectrum of seizure types, and sometimes cause symptomatic epilepsy. The most common risk factors for seizures in transplant recipients is immunosuppressant toxicity. Currently, there isn't a specific treatment involving the transplant patient population. Levetiracetam may be preferable in pediatric patients as it's reliable for liver disease and has advantages in the treatment of postoperative seizures due to its intravenous usage.

Topics: Adolescent; Anticonvulsants; Child; Child, Preschool; Electroencephalography; Female; Humans; Infant; Levetiracetam; Liver Diseases; Liver Transplantation; Magnetic Resonance Imaging; Male; Piracetam; Risk Factors; Seizures

A 34-year-old woman developed a sustained right homonymous hemianopia and episodic visual hallucinations 8 days after liver transplant surgery. Neuro-ophthalmologic examination and perimetry confirmed a right homonymous hemianopia with macular sparing. The patient's vital signs and laboratory values, including a comprehensive metabolic panel and drug levels, were unremarkable. Brain MRI with and without contrast was also unremarkable. A video electroencephalogram revealed frequent, recurrent, left occipitoparietotemporal simple partial seizures associated with episodes of eyelid fluttering, right gaze preference, visual hallucinations, and a dense right hemianopia that persisted interictally. After treatment of the seizures with levetiracetam, perimetry showed resolution of the right homonymous hemianopia. This case demonstrates many classic features of occipital and parietal seizures. It also suggests that, unlike previously reported cases of enduring visual field deficits after cessation of seizures, early diagnosis and management of visual seizures may prevent permanent visual field deficits.

Topics: Adult; Anticonvulsants; Brain; Electroencephalography; Epilepsies, Partial; Female; Hemianopsia; Humans; Illusions; Levetiracetam; Liver Diseases; Liver Transplantation; Magnetic Resonance Imaging; Piracetam; Visual Field Tests