Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. CHAPTER 13 Antiepileptic Drugs

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Epilepsy  Seizure  Brief episode of abnormal electrical activity in the nerve cells of the brain  Convulsion  Involuntary spasmodic contractions of any or all voluntary muscles throughout the body, including skeletal and facial muscles  Epilepsy  Chronic, recurrent pattern of seizures

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Epilepsy (cont’d)  Primary (idiopathic)  Cause cannot be determined  More than 50% of epilepsy cases  Secondary  Distinct cause identified Trauma, infection, cerebrovascular disorder Trauma, infection, cerebrovascular disorder

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Classification of Epilepsy  Partial seizures  Simple seizures  Complex seizures  Generalized seizures  Unclassified seizures  Status epilepticus

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc.

Antiepileptic Drugs  Also known as anticonvulsants  Goals of therapy  To control or prevent seizures while maintaining a reasonable quality of life  To minimize adverse effects and drug-induced toxicity  AED therapy is usually lifelong  Combination of drugs may be used

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Antiepileptic Drugs (cont’d)  Single-drug therapy started before two-drug or multiple-drug therapy is tried  Serum drug concentrations must be measured

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Mechanism of Action AED therapy must:  Prevent generation and spread of excessive electrical discharge from abnormally functioning nerve cells  Protect surrounding normal cells

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Mechanism of Action (cont’d)  Exact mechanism of action not known  AEDs thought to alter movement of sodium, potassium, and calcium ions across nerve cells in the brain  Reduce nerve’s ability to be stimulated  Suppress transmission of impulses from one nerve to the next  Decrease the speed of nerve impulse conduction within a neuron

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Mechanism of Action (cont’d)  Overall effect  Neurons are stabilized  Neuron hyperexcitability is decreased  The spread of excessive nerve impulses is decreased

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Antiepileptic Drugs: Indications  Prevention or control of seizure activity  Long-term maintenance therapy for chronic, recurring seizures  Acute treatment of convulsions and status epilepticus  Other uses

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Antiepileptic Drugs  Numerous adverse effects—vary per drug  Adverse effects often cause the need to change choice of medication

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Antiepileptic Drugs (cont’d)  Barbiturates, such as phenobarbital (Solfoton)  carbamazepine (Tegretol)  valproic acid (Depakote)  Hydantoins, such as phenytoin (Dilantin)

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Antiepileptic Drugs (cont’d)  Succinimides, such as ethosuximide (Zarontin)  Benzodiazepines (clonazepam and clorazepate)  gabapentin (Neurontin)  lamotrigine (Lamictal)  pregabalin (Lyrica)

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Nursing Implications  Assessment, including  Health history, including current medications  Drug allergies  Liver function studies, CBC  Baseline vital signs

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Nursing Implications (cont’d)  Oral drugs  Take regularly, same time each day  Take with meals to reduce GI upset  Do not crush, chew, open extended-release forms  If patient is NPO for a procedure, contact physician regarding AED dosage

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Nursing Implications (cont’d)  Intravenous forms  Follow manufacturer’s recommendations for IV delivery—usually given slowly  Monitor vital signs during administration  Avoid extravasation of fluids  Use only NORMAL SALINE with IV phenytoin

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Nursing Implications (cont’d)  Teach patients to keep a journal to monitor:  Response to AED  Seizure occurrence and descriptions  Adverse effects  A medical alert tag or ID should be worn  AEDs should not be discontinued abruptly  Driving may be impaired until drug levels stabilize

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Nursing Implications (cont’d)  Patients need to know that therapy is long term and possibly lifelong, not a cure

Mosby items and derived items © 2007, 2005, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Nursing Implications (cont’d)  Monitor for therapeutic effects  Seizure activity is decreased or absent  Monitor for adverse effects  Mental status changes, mood changes, changes in LOC or sensorium  Eye problems, visual disorders  Sore throat, fever (blood dyscrasias may occur with hydantoins)  Many others