- •Behavioral problems (e.g., depression) in epilepsy are common but usually of mild severity.
- •30 AED-sensitive items were discerned from the BDI-I, NDDI-E, and FPZ.
- •Items were classified into six scales, constituting the new screening tool “PsyTrack”.
- •PsyTrack subscale scores differed as a function of drug load and presence of AEDs with negative psychotropic effects.
- •Generally, monotherapy seems to be favorable in terms of behavioral adverse effects.
Posts Tagged antiepileptic drugs
[Abstract + References] Therapeutic Drug Monitoring of Antiepileptic Drugs in Women with Epilepsy Before, During, and After Pregnancy – Review
During pregnancy, the pharmacokinetics of an antiepileptic drug is altered because of changes in the clearance capacity and volume of distribution. These changes may have consequences for the frequency of seizures during pregnancy and fetal exposure to antiepileptic drugs. In 2009, a review was published providing guidance for the dosing and therapeutic drug monitoring of antiepileptic drugs during pregnancy. Since that review, new drugs have been licensed and new information about existing drugs has been published. With this review, we aim to provide an updated narrative overview of changes in the pharmacokinetics of antiepileptic drugs in women during pregnancy. In addition, we aim to formulate advice for dose modification and therapeutic drug monitoring of antiepileptic drugs. We searched PubMed and the available literature on the pharmacokinetic changes of antiepileptic drugs and seizure frequency during pregnancy published between January 2007 and September 2018. During pregnancy, an increase in clearance and a decrease in the concentrations of lamotrigine, levetiracetam, oxcarbazepine’s active metabolite licarbazepine, topiramate, and zonisamide were observed. Carbamazepine clearance remains unchanged during pregnancy. There is inadequate or no evidence for changes in the clearance or concentrations of clobazam and its active metabolite N-desmethylclobazam, gabapentin, lacosamide, perampanel, and valproate. Postpartum elimination rates of lamotrigine, levetiracetam, and licarbazepine resumed to pre-pregnancy values within the first few weeks after pregnancy. We advise monitoring of antiepileptic drug trough concentrations twice before pregnancy. This is the reference concentration. We also advise to consider dose adjustments guided by therapeutic drug monitoring during pregnancy if the antiepileptic drug concentration decreases 15–25% from the pre-pregnancy reference concentration, in the presence of risk factors for convulsions. If the antiepileptic drug concentration changes more than 25% compared with the reference concentration, dose adjustment is advised. Monitoring of levetiracetam, licarbazepine, lamotrigine, and topiramate is recommended during and after pregnancy. Monitoring of clobazam, N-desmethylclobazam, gabapentin, lacosamide, perampanel, and zonisamide during and after pregnancy should be considered. Because of the risk of teratogenic effects, valproate should be avoided during pregnancy. If that is impossible, monitoring of both total and unbound valproate is recommended. More research is needed on the large number of unclear pregnancy-related effects on the pharmacokinetics of antiepileptic drugs.
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[Abstract] Antiepileptic drug treatment during pregnancy and delivery in women with epilepsy – A retrospective single center study
Pregnancies in women with epilepsy (WWE) increased significantly during our 11-year study period (41% increase).
Twelve different AEDs were prescribed to WWE during pregnancies in the 11-year period investigated (2005-2015) with Lamotrigine (36.1%), Carbamazepine (25.0%), and Valproic Acid (13.5%) most commonly used.
Valproic acid use was markedly reduced comparing the years 2005-2010 (18.4%) and 2011-2015 (9.4%), a reduction of 48%.
Unfortunately, a trend towards an increase in treating WWE with more than one AED was observed.
[REVIEW] Summary of Antiepileptic Drugs Available in the United States of America – AMERICAN EPILEPSY SOCIETY
The current review summarizes the
main antiepileptic drugs available for
prescription in the United States as of
July 2018. One condensed, and one
expanded, table of the major properties
of 28 AEDs are presented both
to assist clinicians in providing care to
persons with epilepsy and to facilitate
the training of those in health care
This table is not intended to constitute
recommendations, only to provide an
easy reference listing of products on
[Abstract] Affective and behavioral dysfunction under antiepileptic drugs in epilepsy: Development of a new drug-sensitive screening tool
Behavioral problems and psychiatric symptoms are common in patients with epilepsy and have a multifactorial origin, including adverse effects of antiepileptic drugs (AEDs). In order to develop a screening tool for behavioral AED effects, the aim of this study was to identify behavioral problems and symptoms particularly sensitive to AED drug load and the presence/absence of AEDs with known negative psychotropic profiles.
Four hundred ninety-four patients with epilepsy were evaluated who had been assessed with three self-report questionnaires on mood, personality, and behavior (Beck Depression Inventory, BDI; Neurological Disorders Depression Inventory for Epilepsy extended, NDDI-E; and Fragebogen zur Persönlichkeit bei zerebralen Erkrankungen, FPZ). Drug-sensitive items were determined via correlation analyses and entered into an exploratory factor analysis for scale construction. The resulting scales were then analyzed as a function of drug treatment.
Analyses revealed 30 items, which could be allocated to six behavioral domains: Emotional Lability, Depression, Aggression/Irritability, Psychosis & Suicidality, Risk- & Sensation-seeking, and Somatization. Subsequent analysis showed significant effects of the number of AEDs on behavior, as in Emotional Lability (F = 2.54, p = .029), Aggression/Irritability (F = 2.29, p = .046), Psychosis & Suicidality (F = 2.98, p = .012), and Somatization (F = 2.39, p = .038). Affective and behavioral difficulties were more prominent in those patients taking AEDs with supposedly negative psychotropic profiles. These effects were largely domain-unspecific and primarily manifested in polytherapy.
Drug-sensitive behavioral domains and items were identified which qualify for a self-report screening tool. The tool indicates impairments with a higher drug load and when administering AEDs with negative psychotropic profiles. The next steps require normalization in healthy subjects and the clinical validation of the newly developed screening tool PsyTrack along with antiepileptic drug treatment.
Antiepileptic drugs (AEDs) are the mainstay of epilepsy treatment. Since 1989, 18 new AEDs have been licensed for clinical use and there are now 27 licensed AEDs in total for the treatment of patients with epilepsy. Furthermore, several AEDs are also used for the management of other medical conditions, e.g., pain and bipolar disorder. This has led to an increasingly widespread application of therapeutic drug monitoring (TDM) of AEDs, making AEDs among the most common medications for which TDM is performed. The aim of this review is to provide an overview of the indications for AED TDM, to provide key information for each individual AED in terms of the drug’s prescribing indications, key pharmacokinetic characteristics, associated drug-drug pharmacokinetic interactions and the value and the intricacies of TDM for each AED. The concept of the reference range is discussed as well as practical issues such as choice of sample types (total vs free concentrations in blood vs saliva) and sample collection and processing.
The present review is based on published articles and searches in PubMed and Google Scholar, last searched March in 2018, in addition to references from relevant papers.
In total, 171 relevant references were identified and used to prepare this review.
TDM provides a pragmatic approach to epilepsy care in that bespoke dose adjustments are undertaken based on drug concentrations so as to optimize clinical outcome. For the older first generation AEDs (carbamazepine, ethosuximide, phenobarbital, phenytoin, primidone and valproic acid), much data has accumulated in this regard. However, this is occurring increasingly for the new AEDs (brivaracetam, eslicarbazepine acetate, felbamate, gabapentin, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, perampanel, piracetam, pregabalin, rufinamide, stiripentol, sulthiame, tiagabine, topiramate, vigabatrin and zonisamide).
In assessing the effectiveness of prescribed medication there is a strong emphasis on the ability of the patient to adhere to the regime recommended by the clinician. For individuals with epilepsy, adherence to medication is crucial in preventing or minimizing seizures and their cumulative impact on everyday life. Non-adherence to antiepileptic drugs (AEDs) can result in breakthrough seizures many months or years after a previous episode and can have serious repercussions on an individual’s perceived quality of life. Reasons for non-adherence are complex and multilayered. Patients can accidentally fail to adhere through forgetfulness, misunderstanding, or uncertainty about clinician’s recommendations, or intentionally due to their own expectations of treatment, side-effects, and lifestyle choice.
Adherence in epilepsy
Adherence is acting in accordance with advice, recommendations or instruction. Ways that adherence can be optimized;
- Educating individuals and their families and carers in understanding of their condition and the rationale of treatment, reducing the stigma associated with the conditions.
- Using simple medication regimes.
- Positive relationships between healthcare professionals, the individual with epilepsy and their family and /or carers.
- Other measures are; manual telephones follow up, home visits, special reminders, regular appointments/ refill reminders.
While failing to adhere to treatment plans can adversely affect individuals with any general medical condition, Non- adherence to anti-epileptic drugs results to increased risk of status epilepticus (prolonged seizures) resulting into brain damage, SUDEP, risk of injuries, increase rates of admission to hospital due prolonged seizures. The consequences of not taking medication can be more immediate with epilepsy.
Epilepsy as a chronic condition relies heavily on adherence to medical advice in order to maximize an individual’s quality of life by controlling seizures more effectively while avoiding unwanted side-effects. Treatment of those diagnosed with epilepsy the vast majorities are treated with AEDs and approximately 70% can become seizure-free once the most effective regime is followed.
Monotherapy is viewed as the initial and preferential option for treating epilepsy, the choice of drug depending on seizure type and effectiveness of the drug balanced against possible side-effects. It is difficult to find estimates of how many people are on monotherapy or polytherapy at any one point in time.
However, in one of the cases I encountered that of Sarafina Muthoni from Banana, Kiambu County, she was diagnosed with Epilepsy at a very young age in her primary school days. With no history of such a condition in her family, it got everybody thinking what could have gone wrong with their lovely daughter. After days of trying to figure out, the family had to adapt to reality of their daughter living with Epilepsy. She was lucky to have very supportive parents ready to see her through the long journey of treating the condition. The motivation and support from her loved ones to access medication improved her status by far as she continued to adhere to the prescribed treatment. Unfortunately, the support didn’t last long and the burden of continuing with treatment squarely relied on her. This adversely contributed to the beginning of non-adherence to medication for lack of funds to buy drugs. Not only were finances a challenge but also finding a good hospital to comply was a problem.
Muthoni had to live with the sad reality of pain every time she experienced a seizure. Pain which she clearly knew with access to medication the situation could by far be controlled. At the very worse of her situation she found help. Cheshire Disability Services Kenya (CDSK) a Non-Governmental Organization in Kenya whose objective is to empower an inclusive society of persons with disability and develop their full potential to lead a quality life, in partnership with Kenya Association of People with Epilepsy (KAWE) came for Muthonis’ rescue.
Under CDSK’s program to help Epilepsy patients’ access medication and ensure compliance, Muthoni benefited and today she leads a life full of potential and energy as she explores her skills as a beauty and hair stylist.
As we celebrate International Epilepsy Day on Feb 12th 2018, themed on “Life is beautiful”, Muthoni’s story is a highlight of what beauty is all about. Hers’ is just but one of the many inspiring stories to celebrate during this season of Epilepsy Awareness.
Adherence to medication regardless of medical condition remains an important problem in treatment. Factors that have been discussed here – side-effects, drug regime, family support, impact on everyday life, relationship with the clinician – are unlikely to be the only predictors of adherence. While adherence to treatment within the context of epilepsy has been the focus of this review, these factors can equally be applied to various chronic conditions.
Assessment of adherence should be a routine part of management of epilepsy. Further recognition and support should be given to patients who have poor seizure control since they are more likely to be more anxious and have unhelpful illness and treatment beliefs.
Finally, patients may be fully aware of the importance of taking AED medication and the benefits gained by altering their lifestyle choices in order to prevent seizures, but will make a decision about the degree to which they follow advice. Patients only have a small amount of time in contact with the clinician in their “patient role”, after which they return to the practicalities of their everyday routine where their adherence fluctuates based on how they feel their medication affects their quality of life.
Strategies to manage adherence originate from different perspectives. While the medical model may advocate less complex drug regimes, the use of measured pill containers, and minimization of side-effects, the psychosocial model analyzes non-adherence in terms of patient attitudes to medication, stigma, family and peer influences, and ability to manage self care. Neither model can adequately improve adherence independently. Perhaps the best approach is to offer a “menu” of adherence-enhancing strategies. However, what is increasingly clear from both models is that total adherence is an unrealistic goal. The emphasis has shifted away from total adherence towards a compromise with both patient and clinician involved in a joint process of treatment negotiation and decision-making in order to achieve the best outcome for the individual.
A new Cochrane review scrutinizes the efficacy and tolerability of various agents.
New research published in Epilepsia, a journal of the International League Against Epilepsy (ILAE), suggests that an investigational neurological treatment derived from cannabis may alter the blood levels of commonly used antiepileptic drugs. It is important for clinicians to consider such drug interactions during treatment of complex conditions.
Cannabidiol (CBD), a compound developed from the cannabis plant, is being studied as a potential anticonvulsant, and it has demonstrated effectiveness in animal models of epilepsy and in humans. An ongoing open label study (Expanded Access Program) conducted by investigators at the University of Alabama at Birmingham is testing the potential of CBD as a therapy for children and adults with difficult to control epilepsy. The study includes 39 adults and 42 children, all of whom receive CBD.
Because all of the participants are also taking other seizure drugs while they are receiving the investigational therapy, investigators checked the blood levels of their other seizure drugs to see if they changed. “With any new potential seizure medication, it is important to know if drug interactions exist and if there are labs that should be monitored while taking a specific medication,” said lead author Tyler Gaston, MD.
Dr. Gaston and her colleagues found that there were significant changes in levels of the drugs clobazam (and its active metabolite N-desmethylclobazam), topiramate, and rufinamide in both adults and children, and zonisamide and eslicarbazepine in adults only. Except for clobazam/desmethylclobazam, however, the drug levels did not change outside of the normally accepted range. In addition, adult participants in the study taking clobazam reported sedation more frequently.
Tests also showed that participants taking valproate and CBD had higher ALT and AST (liver function tests) compared with participants not taking valproate. Very high ALT and AST indicate abnormal liver function, but significant ALT and AST elevation occurred only in a mall number of participants (4 children and 1 adult), and the levels returned to normal after discontinuation of valproate and CBD.
“While the interaction between CBD and clobazam has been established in the literature, there are currently no published human data on CBD’s potential interactions with other seizure medications,” said Dr. Gaston. “However, given the open label and naturalistic follow-up design of this study, our findings will need to be confirmed under controlled conditions.”
The findings emphasize the importance of monitoring blood levels of antiepileptic drugs as well as liver function during treatment with CBD. “A perception exists that since CBD is plant based, that it is natural and safe; and while this may be mostly true, our study shows that CBD, just like other antiepileptic drugs, has interactions with other seizure drugs that patients and providers need to be aware of,” said Dr. Gaston.
Article: Interactions between cannabidiol and commonly used antiepileptic drugs, Tyler E. Gaston, E. Martina Bebin, Gary R. Cutter, Yuliang Liu, Jerzy P. Szaflarski, and for the UAB CBD Program, Epilepsia, doi: 10.1111/epi.13852, published online 6 August 2017.