Although Coronavirus disease 2019 (COVID-19) vaccinations are generally recommended for persons with epilepsy (PwE), a significant vaccination gap remains due to patient concerns over the risk of post-vaccination seizure aggravation (PVSA). In this single-centre, retrospective cohort study, we aimed to determine the early (7-day) and delayed (30-day) risk of PVSA, and to identify clinical predictors of PVSA among PwE. Adult epilepsy patients aged ≥18 years without a history of COVID-19 infection were recruited from a specialty epilepsy clinic in early 2022. Demographic, epilepsy characteristics, and vaccination data were extracted from a centralized electronic patient record. Seizure frequency before and after vaccination, vaccination-related adverse effects, and reasons for or against vaccination were obtained by a structured questionnaire. A total of 786 PwEs were included, of which 27.0% were drug-resistant. At the time of recruitment, 74.6% had at least 1 dose of the COVID-19 vaccine. Subjects with higher seizure frequency (p < 0.0005), on more anti-seizure medications (p = 0.004), or had drug-resistant epilepsy (p = 0.001) were less likely to be vaccinated. No significant increase in seizure frequency was observed in the early (7 days) and delayed phases (30 days) after vaccination in our cohort. On the contrary, there was an overall significant reduction in seizure frequency 30 days after vaccination (1.31 vs. 1.89, t = 3.436; p = 0.001). This difference was seen in both types of vaccine (BNT162b2 and CoronaVac) and drug-resistant epilepsy, but just missed significance for the second dose (1.13 vs. 1.87, t = 1.921; p = 0.055). Only 5.3% had PVSA after either dose of vaccine. Higher pre-vaccination seizure frequency of ≥1 per week (OR 3.01, 95% CI 1.05-8.62; p = 0.04) and drug-resistant status (OR 3.32, 95% CI 1.45-249 7.61; p = 0.005) were predictive of PVSA. Meanwhile, seizure freedom for 3 months before vaccination was independently associated with a lower risk of PVSA (OR 0.11, 95% CI 0.04-0.28; p < 0.0005). This may guide epilepsy treatment strategies to achieve better seizure control for at least 3 months prior to vaccination. As COVID-19 shifts to an endemic phase, this study provides important data demonstrating the overall safety of COVID-19 vaccinations among PwE. Identification of high-risk patients with subsequent individualized approaches in treatment and monitoring strategies may alleviate vaccination hesitancy among PwE.

OBJECTIVE: The objective of this study was to conduct a systematic review of research pertaining to the COVID-19 vaccine and its association with neurological complications.
METHODS: We performed a comprehensive search of the literature using Google Scholar, PubMed, and NCBI databases from December 2021 to December 2022. For Google Scholar, PubMed, and NCBI databases we used the following key search terms: \"neurological adverse effects\", \"COVID-19 vaccination\", \"SARS-CoV-2\", CNS complications, and CNS adverse effects. Two reviewer authors individually searched and assessed the titles and abstracts of all articles. The third reviewer resolved the disagreement between them. Data were documented regarding title, study location, type of study, type of COVID-19 vaccine, type of neurological complications/adverse effects, and sample size.
RESULTS: From our findings, it is confirmed that these neurological complications like GuillainBarre syndrome (23.6%), Neuromyelitis Optica spectrum disorder (5.5%), Neuropathy (6.9%), Transverse Myelitis (8.3%) and Acute disseminated Encephalomyelitis (4.1%) are majorly affected in most of the people. The increase in risks associated with SARS-CoV-2 infection far outweighs any previously reported associations with vaccination.
CONCLUSIONS: We found no safety signal was observed between COVID-19 vaccines and the immune-mediated neurological events. Before assuming a causal relationship, the side effects of the COVID-19 vaccine should first be carefully examined to rule out known associated factors. Symptom onset was within two weeks of vaccination in the majority of cases; as such, this seems to be a high-risk period warranting vigilance.

Dextromethorphan is a distant derivative of morphine, used as an antitussive agent indicated in standard care for various infections and respiratory conditions ranging from the common cold (rhinoviruses) to severe acute respiratory illness (SARI). Being a derivative of morphine, a natural central nervous system (CNS) depressant, dextromethorphan produces little to no action on CNS when ingested in the prescription dosage. We present a case of a 64-year-old female patient, a known case of ischemic heart disease post angioplasty and stenting to the left anterior descending artery (LAD), with heart failure with reduced ejection fraction (HFrEF), diabetes, hypertension, chronic kidney disease, and hypothyroidism who developed extrapyramidal symptoms post dextromethorphan administration. The incidence of dextromethorphan-induced dystonia is unknown, and the literature review suggests 4 case reports indicating dextromethorphan-induced dystonia, and each of those reports is a case of either accidental overdose or overdose in substance abuse disorder. No cases of these CNS side effects are described among adults with a therapeutic dose of dextromethorphan. This case report serves to sensitize the clinician about this rare occurrence.

Immune checkpoint inhibitors (ICPIs) and chimeric antigen receptor (CAR) T-cell constitute recently approved novel therapies targeted to treat a wide number of malignancies. Both the treatments modulate the immune system and can cause a number of immune-related adverse events (irAEs), including polyendocrinopathies, gastrointestinal and neurological complications. This literature review focuses on the neurological side effects of these therapies as these are uncommon and alter the course of the treatment. Neurological complications involve the peripheral and central nervous system, including polyneuropathy, myositis, myasthenia gravis, demyelinating polyradiculopathy, myelitis, and encephalitis. If early recognized, the neurological complications can be treated effectively with steroids to reduce the potential of short-term and long-term complications. Therefore, early identification and treatment of irAEs are needed to optimize the outcomes associated with ICPI and CAR T-cell therapies.

The COVID-19 pandemic has led to unprecedented demand on the global healthcare system. Remarkably, at the end of 2021, COVID-19 vaccines received approvals for human use in several countries worldwide. Since then, a solid base for response in the fight against the virus has been placed. COVID-19 vaccines have been shown to be safe and effective drugs. Nevertheless, all kinds of vaccines may be associated with the possible appearance of neurological complications, and COVID-19 vaccines are not free from neurological side effects. Neurological complications of COVID-19 vaccination are usually mild, short-duration, and self-limiting. However, severe and unexpected post-vaccination complications are rare but possible events. They include the Guillain-Barré syndrome, facial palsy, other neuropathies, encephalitis, meningitis, myelitis, autoimmune disorders, and cerebrovascular events. The fear of severe or fatal neurological complications fed the \"vaccine hesitancy\" phenomenon, posing a vital communication challenge between the scientific community and public opinion. This review aims to collect and discuss the frequency, management, and outcome of reported neurological complications of COVID-19 vaccines after eighteen months of the World Health Organization\'s approval of COVID-19 vaccination, providing an overview of safety and concerns related to the most potent weapon against the SARS-CoV-2.

Clozapine is the gold standard for treatment-resistant schizophrenia. Serious and even life-threatening adverse effects, mostly granulocytopenia, myocarditis, and constipation, are of great clinical concern and constitute a barrier to prescribing clozapine, thus depriving many eligible patients of a lifesaving treatment option. Interestingly, clozapine presents variable pharmacokinetics affected by numerous parameters, leading to significant inter- and intra-individual variation. Therefore, therapeutic drug monitoring of plasma clozapine levels confers a significant benefit in everyday clinical practice by increasing the confidence of the prescribing doctor to the drug and the adherence of the patient to the treatment, mainly by ensuring effective treatment and limited dose-related side effects. In the present systematic review, we aimed at identifying how a full range of adverse effects relates to plasma clozapine levels, using the Jadad grading system for assessing the quality of the available clinical evidence. Our findings indicate that EEG slowing, obsessive-compulsive symptoms, heart rate variability, hyperinsulinemia, metabolic syndrome, and constipation correlate to plasma clozapine levels, whereas QTc, myocarditis, sudden death, leucopenia, neutropenia, sialorrhea, are rather unrelated. Rapid dose escalation at the initiation of treatment might contribute to the emergence of myocarditis, or leucopenia. Strategies for managing adverse effects are different in these conditions and are discussed accordingly.

Medication errors may occur at any point during patient care in the health care system. Drug interaction in known with macrolide antibiotics and ranolazine and is primarily related to effects on the cytochrome P4503A (CYP3A) metabolic pathway. This case highlights medication errors that resulted in rare debilitating neurological adverse effects of ranolazine in an elderly due to drug interaction with clarithromycin.

Iatrogenic disease is one of the most frequent causes of hospital admissions and constitutes a growing public health problem. The most common type of iatrogenic neurologic disease is pharmacologic, and the central and peripheral nervous systems are particularly vulnerable. Despite this, iatrogenic disease is generally overlooked as a differential diagnosis among neurologic patients. The clinical picture of pharmacologically mediated iatrogenic neurologic disease can range from mild to fatal. Common and uncommon forms of drug toxicity are comprehensively addressed in this chapter. While the majority of neurologic adverse effects are listed and referenced in the tables, the most relevant issues are further discussed in the text.