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Mosby items and derived items © 2005, 2002 by Mosby, Inc.
CHAPTER 13
Antiepileptic Agents
Mosby items and derived items © 2005, 2002 by Mosby, Inc.
Table 13-1 Antiepileptic Drugs of Choice
Mosby items and derived items © 2005, 2002 by Mosby, Inc.
Epilepsy
• Seizure– Brief episode of abnormal electrical activity in 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 © 2005, 2002 by Mosby, Inc.
Epilepsy (cont'd)
• Primary (idiopathic)– Cause cannot be determined– More than 50% of epilepsy cases
• Secondary– Distinct cause identified
• Trauma, infection, cerebrovascular disorder
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Classification of Epilepsy
• Partial seizures– Simple seizures– Complex seizures
• Generalized seizures
• Unclassified seizures
• Status epilepticus
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Box 13-1 International Classification of Seizures
Mosby items and derived items © 2005, 2002 by Mosby, Inc.
Antiepileptic Agents
• Also known as Antiepileptic Drugs (AEDs)• Goals of therapy
– To control or prevent seizures while maintaining a reasonable quality of life
– To minimize side effects and drug-induced toxicity
• AED therapy is usually lifelong• Combination of agents may be used
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Antiepileptic Agents
• Single-drug therapy started before two-drug and multiple-drug therapy is tried
• Serum drug concentrations must be measured
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Mechanism of Action
AED therapy must:– Prevent generation and spread of
excessive electrical discharge from abnormally functioning nerve cells
– Protect surrounding normal cells
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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
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Mechanism of Action (cont'd)
• Overall effect– Neurons are stabilized– Neuron hyperexcitability is decreased– The spread of excessive nerve impulses
is decreased
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Antiepileptic Agents:Indications
• Prevention or control of seizure activity
• Long-term maintenance therapy for chronic, recurring seizures
• Acute treatment of convulsions and status epilepticus
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Antiepileptic Agents
• Numerous side effects—vary per agent
• Side effects often cause the need to change choice of medication
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Antiepileptic Agents
• Barbiturates, such as phenobarbital (Solfoton)
• carbamazepine (Tegretol)
• valproic acid (Depakote)
• felbamate (Felbatol)
• Hydantoins, such as phenytoin (Dilantin)
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Antiepileptic Agents (cont'd)
• Succinimides, such as ethosuximide (Zarontin)
• Benzodiazepines (clonazepam and clorazepate)
• gabapentin (Neurontin)
• lamotrigine (Lamictal)
• Several other miscellaneous agents
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Nursing Implications
• Assessment, including– Health history, including current
medications– Drug allergies– Liver function studies, CBC– Baseline vital signs
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Nursing Implications
• Oral agents– Take regularly, same time each day– Take with meals to reduce GI upset– Do not crush, chew, open extended-
release forms
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Nursing Implications
• Intravenous forms– Follow manufacturer’s recommendations
for IV delivery—usually given slowly– Monitor VS during administration– Avoid extravasation of fluids– Use only NORMAL SALINE with IV
phenytoin
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Nursing Implications
• Teach patients to keep a journal to monitor:– Response to AED– Seizure occurrence and descriptions– Side effects
• A medical alert tag or ID should be worn• AEDs should not be discontinued abruptly• Driving may be impaired until drug levels
stabilize
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Nursing Implications
• Patients need to know that therapy is long term and possibly lifelong, not a cure
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Nursing Implications
• Monitor for therapeutic effects– Seizure activity is decreased or absent
• Monitor for side 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