Carbamazepine Induced CNS Adverse Effects: A Case Report

Background: Epilepsy is a chronic neurological disorder that affects people worldwide. The main goal of treatment is to achieve seizure control without adverse effects. Carbamazepine is a commonly used sedative antiepileptic medication in many countries. It is mainly indicated for the treatment of partial seizures with complex symptomatology (e.g., psychomotor, temporal lobe), generalized tonicclonic seizures (grand mal), and mixed seizure patterns, which include the seizure types listed or other partial or generalized seizures and also for the treatment of trigeminal neuralgia. Carbamazepine is reported to cause a range of deleterious and erratic side effects at therapeutic and toxic doses. Drug rash with eosinophilia and systemic symptoms (DRESS) syndrome is an uncommon but serious hypersensitivity drug reaction most frequently associated with anti-epileptics. Common adverse effects may include drowsiness, dizziness, headaches and migraines, motor coordination impairment, nausea, vomiting, and/or constipation. Serious side effects may include skin rashes, decreased bone marrow function, suicidal thoughts, or confusion. CASE REPORT: We report a case of carbamazepine-induced adverse effects in 24 years young female patient who has presented with vomiting 2-3 episodes, dizziness, drowsiness and slurring of speech. Her past history revealed that she is a known case of seizure disorder since 4 years and on treatment with Tablet Phenytoin 100 mg BID and stopped taking medication. She had last episode of seizure 6 months back. Based on the presenting signs and symptoms, her condition was diagnosed as Carbamazepine-induced CNS adverse effects. The symptoms improved significantly after the offending drug was withdrawn. Alternatively, she was started on oral Phenytoin 100 mg BID. Naranjo and WHO causality assessment was done, indicating a probable relationship between the patient’s symptoms and her use of carbamazepine. Patient was later managed with IV fluids, intravenous Phenytoin of 800 mg in 100 ml NS, intravenous ondansetron. After 3 days of therapy symptomatic relief was observed and patient was discharged. CONCLUSION: This case report highlights the adverse drug reactions of carbamazepine and the need of regular monitoring in patients on long-term therapy. Jaladi Himaja *1 , Battu Rakesh *1 Pharm.D Intern, Department of Pharmacy Practice, Bharathi College of Pharmacy, Bharathinagara, K.M. Doddi, Mandya, Karnataka, India-571422. Submission: 10 January 2017 Accepted: 15 January 2017 Published: 25 January 2017 www.ijppr. humanjournals.com Citation: Jaladi Himaja et al. Ijppr.Human, 2017; Vol. 8 (2): 209-217. 210 INTRODUCTION Epilepsy is a common neurological disorder. The main goal of treatment is to achieve seizure control without adverse effects 1 . Epilepsy is a relatively common condition characterized by a tendency for recurrent seizures, which is due to the disturbance of spread of electrical discharge of the cortical neurons. Up to 80% of people with epilepsy are able to control their condition with anti-epileptic drugs (AEDs). The type of drug therapy prescribed depends on the type of seizure, the underlying cause of epilepsy, age of the patient and possible side effects. Treatment usually starts with one drug at a low dose. The dose is then increased slowly. In most patients, epilepsy remits over a period of years and drug therapy may be withdrawn slowly 2 . According to World Health Organization (WHO) statistics, approximately 50 million people worldwide have epilepsy. In India, the prevalence rate of epilepsy ranges between 4.15 and 7.03 per 1000 population. In newly diagnosed cases, 60% are partial and 40% generalized. Epilepsy adversely affects the psychosocial status and quality of life of patients. General approaches for epilepsy management involves identification of goals and development of care plan 3 . Carbamazepine (kar" ba maz' e-peen) is an iminostilbene that is chemically related to tricyclic antidepressants and unrelated in structure to other anticonvulsants. Carbamazepine suppresses spread of seizure activity by reduction in the post-tetanic potentiation of synaptic transmission. The ultimate goal is seizures freedom without adverse effects of medication and improved quality of life. Epilepsy often requires long-term AED therapy. However, prolonged AED administration is associated with a number of problems such as behavioral and psychiatric disorders, metabolic and endocrine disorders, idiosyncratic reactions, and drug interaction effects 4 . All antiepileptic drugs have a relatively high incidence of adverse reactions. They are a major cause of discontinuing treatment. Many adverse reactions are dose related and predictable and can be minimized by commencing therapy with a low dose and with gradual escalation of the dose and dose reduction if symptoms persist. With respect to carbamazepine, particularly at the start of treatment or if the initial dose is too high, the following certain types of adverse reaction can occur very commonly (>10%) or commonly (>1% to <10%). www.ijppr. humanjournals.com Citation: Jaladi Himaja et al. Ijppr.Human, 2017; Vol. 8 (2): 209-217. 211  CNS (dizziness, ataxia, drowsiness, fatigue, headache, diplopia, accommodation disorders).  Skin (allergic skin reactions, urticaria).  GI Disturbances (nausea and vomiting, dry mouth).  Blood Dyscrasias (leucopenia, thrombocytopenia).  Liver Disturbances (elevated gamma-glutamyl transferase and alkaline phosphatase). It is generally recommended that white blood cell counts and liver functions tests are conducted before commencing treatment and periodically thereafter.  Endocrine System and Metabolism (edema, fluid retention, weight increase, hyponatremia). Occurrence of CNS adverse effects may be a manifestation of relative overdosage or significant fluctuation in plasma levels. Monitoring of plasma levels may be useful as is division of the daily dosage into 3-4 doses. Idiosyncratic reactions can also occur 5,6,7,8 . These usually arise early in treatment but can occur at any time and are potentially serious (e.g. Stevens Johnson Syndrome, exfoliative dermatitis, hepatitis). The toxic effects of chronic use may present with wide variety of clinical symptoms and signs. Here we report a case of Carbamazepine toxicity in an adolescent female presenting with multiple adverse drug reactions (ADRs). The objective of this report is to describe a case of CNS adverse drug reactions caused by carbamazepine and is important for the clinicians to be aware of its presentation. It is important to identify the causative agent as early as possible and withdrawal of it is necessary for critical management. We report a case of Carbamazepine-Induced CNS adverse drug reactions induced in 24 years adult female patient who had past history of seizure disorder since 4 years and on treatment with Tablet Phenytoin 100 mg BID and stopped taking medication. She had last episode of seizure 6 months back. The following case report demonstrates the necessity of prompt recognition and initiation of appropriate therapy in preventing the potential sequelae of Carbamazepine toxicity. www.ijppr. humanjournals.com Citation: Jaladi Himaja et al. Ijppr.Human, 2017; Vol. 8 (2): 209-217. 212 Case presentation A 24-year adult female visited the outpatient department of general medicine unit of Mandya Institute of Medical Sciences and Teaching Hospital, Mandya, Karnataka, India. She presented with vomiting 2-3 episodes, dizziness, drowsiness and slurring of speech. She past history revealed that she is a known case of seizure disorder since 4 years and on treatment with Tablet Phenytoin 100 mg BID and stopped taking medication. She had last episode of seizure 6 months back. No other significant past medical history and drug allergies.