CHAPTER 13
Antiepileptic Agents
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Table 13-1 Antiepileptic Drugs of Choice
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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
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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
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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 twodrug 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 extendedrelease 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
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