Drugs for Seizures Chapter 15 15. Antidepressant / Anxiolytic Antidepressant / Anxiolytic escitalopram (Lexapro) Tri-Cyclic Antidepressa nt MAOIs Benzodiazepines

Drugs for SeizuresChapter 15

15

Antidepressant /Anxiolytic

Antidepressant /Anxiolytic

escitalopram (Lexapro)Tri-Cyclic Antidepressa

nt

Tri-Cyclic Antidepressa

nt

MAOIsMAOIs

BenzodiazepinesBenzodiazepines lorazepam (Ativan)diazepam (Valium)

GABA AntagonistGABA

AntagonistA zolpidem (Ambien)

Phenytoin-LikeDrugs

Phenytoin-LikeDrugs

SuccinimidesSuccinimides

BarbituratesBarbiturates phenobarbital (Luminal)

phenytoin (Dilantin)valproic acid (Depakote)

ethosuximide (Zarontin)

PhenothiazinesPhenothiazines chlorpromazine (Thorazine)

Non-Phenothiazines

Non-Phenothiazines

halperidol (Haldol)

Atypical Antipsychotics

Atypical Antipsychotics risperidone (Risperdal)

OpioidsOpioids

Opioid Antagonists

Opioid Antagonists

naloxone (Narcan)

morphine (Infumorph)

SalicylatesSalicylates aspirin (ASA)

NSAIDsNSAIDs ibuprofen (Motrin)

Non-OpioidNon-Opioid acetaminophen (Tylenol)

Central ActingCentral Acting tramadol (Ultram)

Anti-MigraineAnti-Migraine ergotamine (Cafergot)Sumatriptan (Imitrex)

OVERVIEW:Neuro System

Antiseizure Pharmacotherapy• Goal: suppress neuronal activity enough to

prevent abnormal or repetitive firing• Drugs act through three mechanisms:

• Stimulating an influx of chloride ions• Delaying an influx of sodium• Delaying an influx of calcium

• Directed at controlling movement of electrolytes across neuronal membranes or affecting neurotransmitter balance

• Some drugs act by more than one mechanism

Pharmacotherapy Illustrated: Model of the GABA Receptor–Chloride Channel Molecules in Relationship to Antiseizure Pharmacotherapy

Barbiturates and GABA Agents

• Monitor Patient’s condition• Liver and kidney function• Pregnancy Category D• Common side effects

Patient Teaching

• Use reliable contraception• Immediately report pregnancy• Report excessive signs of bleeding• Report drowsiness and bone pain

Drugs that Potentiate GABA Action

• Act by changing the action of gamma-aminobutyric acid (GABA), the primary inhibitory neurotransmitter in the brain

• Predominate effect of GABA potentiation is CNS depression

Benzodiazepines—Schedule IV Drug

• Monitor for drug-abuse potential• Pregnancy risk—Pregnancy Category D• Contraindicated in narrow-angle glaucoma• Respiratory depression may result with other CNS

depressants.• Common side effects include dizziness, drowsiness• Overdose—give flumazenil (Romazicon)

Patient Teaching

• Avoid alcohol, OTC drugs, and herbal medications• Avoid nicotine• Avoid driving and hazardous activities• Rebound seizures if discontinued abruptly• Take with food• Drug often used illegally

Hydantoin and Phenytoin-like Drugs

• Monitor serum-drug levels• Monitor for signs of toxicity• Monitor for blood dyscrasias and bleeding disorders• Monitor liver and kidney function• Fatal hepatotoxicity can occur

Hydantoin and Phenytoin-like Drugs Contraindications

• Patients with hypersensitivity to hydantoin products should be cautious.

• Rash, seizures due to hypoglycemia, sinus bradycardia, and heart block

Patient Teaching

• Routine labs for serum level• Routine labs for liver and kidney function• Immediately report signs of toxicity• Immediately report unusual bleeding• Immediately report liver or brain disease• Immediately report heart block, hypoglycemia, or

pregnancy

Succinimides

• Do not abruptly withdraw medication• Use with caution with antiseizure medications,

phenothiazines, and antidepressants• Pregnancy risk—pregnancy Category C

Common Adverse Reactions

• Drowsiness, headache, fatigue, dizziness• Depression or euphoria• Nausea, vomiting, weight loss• Abdominal pain

Life-Threatening Reactions• Severe mental depression with suicide intent• Stevens-Johnson syndrome• Blood dyscrasias

Patient Teaching

• Immediately report mood changes or suicidal thoughts• Avoid driving and hazardous activities• Do not suddenly stop taking• Take with food• Report symptoms of fever or sore throat• Report weight loss and anorexia

Dosage Procedure

• Start with smallest initial dose• Add additional drugs, if necessary• Ensure compatibility with other medications• Monitor serum-drug levels

Withdrawal of Antiseizure Medications

• Should be seizure free at least three years• Withdraw gradually over several months• Resume medications if seizures return• Be aware of rebound seizures

Drugs That Potentiate GABA Action

• Barbiturates• Benzodiazepines• Miscellaneous GABA agents

Barbiturates

• Prototype drug: phenobarbital (Luminal)• Mechanism of action: changing the action of GABA

• Primary use: controlling seizures• Adverse effects: dependence, drowsiness, vitamin deficiencies, laryngospasm

Prototype Drug: Phenobarbital (Luminal)

Benzodiazepines • Prototype drug: diazepam (Valium)• Mechanism of action: similar to that of

barbiturates but safer• Primary use: for short-term seizure control• Adverse effects: drowsiness and dizziness

Prototype Drug: Diazepam (Valium)

Diazepam Animation

Click here to view an animation on the topic of diazepam.

Hydantoins• Prototype drug: phenytoin (Dilantin)• Mechanism of action: to densitize sodium

channels• Primary use: treating all types of epilepsy

except absence seizures• Adverse effects: CNS depression, gingival

hyperplasia, skin rash, cardiac dysrhythmias, and hypotension

Prototype Drug: Phenytoin (Dilantin)

Prototype Drug: Phenytoin (Dilantin)

Phenytoin-Like Drugs

• Prototype drug: Valproic acid (Depakene)• Mechanism of action: to desensitize sodium channels

• Primary use: for absence seizures• Adverse effects: limited CNS depression, visual disturbances, ataxia, vertigo, headache

• Additional adverse reactions: gastrointestinal effects, hepatotoxicity, pancreatitis

Valproic Acid Animation

Click here to view an animation on the topic of valproic acid.

Prototype Drug: Valproic Acid (Depakene, Depakote)

Succinimides

• Prototype drug: ethosuximide (Zarontin)• Mechanism of action: suppress calcium influx • Primary use: for absence seizures• Adverse effects: rare but include drowsiness, dizziness, lethargy

• Very rare but serious side effects: systemic lupus erythematosis, leukopenia, aplastic anemia, Stevens-Johnson syndrome

Prototype Drug: Ethosuximide (Zarontin)

Drugs That Potentiate GABA Action

• Include barbiturates, benzodiazepines, and miscellaneous GABA agents

• Suppress the firing ability of neurons

Treating Seizures with Barbituates• Low margin for safety• High potential for dependence, and they cause• Profound CNS depression• Overall effective against all major seizure types

except absence seizures

Examples of Barbiturates • Phenobarbital (Luminal)• Amobarbital (Amytal)• Secobarbital (Seconal)• Pentobarbital (Nembutal)

Treating Seizureswith Benzodiazepines

• Indications include absence seizures and myoclonic seizures

• Tolerance may develop quickly• one of most widely prescribed classes, used

also for anxiety, skeletal muscle spasms, and alcohol withdrawal symptoms

Examples of Benzodiazepines• Clonazepam (Klonopin)• Clorazepate (Tranxene)• Lorazepam (Ativan)• Diazepam (Valium)

Newer GABA-related Drugs

• Gabapentin (Neurontin)• Pregabalin (Lyrica)• Tiagabine (Gabitril)• Topiramate (Topamax)

Hydantoin and Newer Drugs

• Delay an influx of sodium ions across neuronal membranes

• Sodium movement is factor that determines whether neuron will undergo an action potential

• Sodium channels are not blocked; they are just desensitized

Treating Seizures With Hydantoins and Related Drugs

• Useful in treating all types of epilepsy except absence seizures

• Provides effective seizure suppression, without the abuse potential or CNS depression associated with barbiturates

• Phenytoin-related drugs used less frequently

Examples of Hydantoins• Phenytoin (Dilantin)—most common • Fosphenytoin (Cerebyx)

Examples of Phenytoin-like Drugs

• Carbamazepine (Tegretol)—tonic-clonic and partial seizures

• Felbamate (Felbatol)• Lamotrigine (Lamictal)• Valproic acid (Depakene, Depakote)—absence

seizures • Zonisamide (Zonegran)

Treating Seizures with Succinimides

• Suppress seizures by delaying calcium influx into neurons

• Generally only effective against absence seizures

• Ethosuximide (Zarontin) is the most commonly prescribed drug in this class

Succinimides• Examples of succinimides

• Ethosuximide (Zarontin)• Methsuximide (Celontin)• Phensuximide (Milontin)

NCLEX-RN ReviewQuestion 1

The nurse evaluates patient teaching related to causes of seizures. Further teaching is needed if the patient makes which of the following statements?

1. “Seizures can be caused by inflammation of the brain.”

2. “Seizures can be caused by low blood sugar.” 3. “My relative had seizures because of a large

tumor growing in his muscles.” 4. “Seizures may occur after a head injury.”

NCLEX-RN ReviewQuestion 1 – Answer

1. “Seizures can be caused by inflammation of the brain.”

2. “Seizures can be caused by low blood sugar.”

3. “My relative had seizures because of a large tumor growing in his muscles.”

4. “Seizures may occur after a head injury.”

NCLEX-RN ReviewQuestion 1 – Rationale

Rationale: Seizures may be caused by inflammation, head injuries, or low blood sugar levels. Rapid-growing, space-occupying lesions in the brain, which increase intracranial pressure, may cause seizures, but not tumors, within the muscles.

NCLEX-RN ReviewQuestion 2The nursing student asks the nurse to explain the action of the antiseizure medication, phenytoin. The nurse explains the mechanism of action as:

1. Suppression of the influx of chloride into the neuron

2. Stimulation of the influx of calcium into the neuron 3. Suppression of the influx of sodium into the neuron 4. Stimulation of calcium and sodium needed to

suppress seizure activity


1. Suppression of the influx of chloride into the neuron

2. Stimulation of the influx of calcium into the neuron

3. Suppression of the influx of sodium into the neuron

4. Stimulation of calcium and sodium needed to suppress seizure activity


Rationale: The influx of sodium into a neuron enhances neuronal activity. The delay of an influx suppresses neurotransmitter frequency.


The nurse recognizes that several chemicals inhibit neurotransmitter function in the brain. The primary inhibitory transmitter in the brain is:

1. Sodium 2. GABA 3. Chloride 4. Calcium


1. Sodium

2. GABA

3. Chloride

4. Calcium


Rationale: GABA drugs mimic GABA by stimulating the influx of chloride ions into the neuron, leading to the suppression of neuron firing.

NCLEX-RN ReviewQuestion 4The patient, age 8, is prescribed valproic acid (Depakene) for treatment of a seizure disorder. The nurse should monitor the patient closely for:

1. Hyperthermia 2. Vitamin B deficiency 3. Restlessness and agitation 4. Respiratory distress


1. Hyperthermia

2. Vitamin B deficiency

3. Restlessness and agitation

4. Respiratory distress


Rationale: Valproic acid may produce an idiosyncratic response in children, including restlessness and psychomotor agitation.


Discharge teaching for a patient receiving carbamazepine (Tegretol) should include:

1. Monitoring blood glucose and reporting decreased levels

2. Expecting a discoloration of contact lenses 3. Immediately reporting unusual bleeding or

bruises to the health care provider4. Expecting a green discoloration of urine


1. Monitoring blood glucose and reporting decreased levels

2. Expecting a discoloration of contact lenses

3. Immediately reporting unusual bleeding or bruises to the health care provider

4. Expecting a green discoloration of urine


Rationale: Carbamazepine affects vitamin K metabolism and may lead to blood dyscrasias and bleeding.

PathophysiologyOf Seizures

/Discussion

Seizures

• Abnormal or uncontrolled neuronal discharges in the brain• Affect

• Consciousness• Motor activity• Sensation

• Symptom of an underlying disorder

Convulsion

• Involuntary violent spasm of large muscles of face, neck, arms, and legs

• Not synonymous with seizure

Different etiologies of seizure activity• Most common serious neurologic problem

affecting children• May present as an acute situation, or they may

occur on a chronic basis

Known Causes of Seizures

• Infectious diseases• Trauma• Metabolic disorders• Vascular diseases• Pediatric disorders• Neoplastic disease

Additional Known Causes of Seizures

• Medications• High doses of local anesthetics• Eclampsia• Drug abuse• Withdrawal syndromes from alcohol or sedative-hypnotic

drugs

Pregnancy and Epilepsy

• Several antiseizure drugs decrease effectiveness of oral contraceptives

• Most antiseizure drugs are pregnancy category D• Eclampsia - severe hypertensive disorder of

pregnancy, characterized by seizures, coma, and perinatal mortality

Epilepsy

• Seizures occurring chronically• International Classification of Epileptic Seizures

• Partial (focal)• Generalized• Special epileptic syndromes

Seizures in Neonates, Infants, and Children

• Congenital abnormalities of CNS• Perinatal brain injury• Metabolic imbalances

Later-Childhood Etiology

• CNS infections• Neurological degenerative disorders• Inherited epilepsies

Adult Etiology

• Cerebral trauma• Cerebrovascular disorders• Neoplastic disease

Signs and Symptoms of Seizures

• Related to area of brain with abnormal activity• International Classification of Epileptic

Seizures: classifies seizures

Simple Partial Seizures • Olfactory, auditory, and visual hallucinations• Intense emotions• Twitching of arms, legs, and face

Complex Partial (psychomotor) Seizures

• Aura (preceding)• Brief period of confusion or sleepiness afterward

with no memory of seizure (postictal confusion)• Fumbling with or attempting to remove clothing• No response to verbal commands

Generalized Seizures• Absence (petit mal)• Atonic (drop attacks)• Tonic-clonic (grand mal)

Absence Seizures• Lasting a few seconds• Seen most often in children (child stares into space,

does not respond to verbal stimulation, may have fluttering eyelids or jerking)

• Misdiagnosed often (especially in child) as ADD or daydreaming

Atonic Seizures• Falling or stumbling for no reason• Lasting a few seconds

Tonic-Clonic Seizures• Preceeded by aura• Intense muscle contraction (tonic phase) followed

by alternating contraction and relaxation of muscles (clonic phase)

• Crying at beginning as air leaves lungs; loss of bowel/bladder control; shallow breathing with periods of apnea; usually lasting 1–2 minutes

• Disorientation and deep sleep after seizure (postictal state)

Special Syndromes

• Febrile seizures• Myoclonic seizures• Status epilepticus

Febrile Seizures• Tonic–clonic activity lasting 1–2 minutes• Rapid return to consciousness• Occurs in children usually between 3 months

and 5 years of age

Myoclonic Seizures• Large jerking movements of a major muscle

group, such as an arm• Falling from a sitting position or dropping what

is held

Status Epilepticus• Considered a medical emergency• Continuous seizure activity, which can lead to

coma and death

Choice of Drug Depends Upon• Type of seizure• Patient’s history and diagnostic studies• Associated pathologies

Once Medication is Selected• Patient placed on low initial dose• Amount gradually increased• If seizure activity remains, different medication

added in small increments• Newer antiseizure drugs have less adverse side

effects than older drugs• Most cases require only a single drug

New FDA Warnings• Study included patients with epilepsy, bipolar

disorder, psychoses, migraines, and neuropathic pain

• Popular antiseizure examples found to almost double risk of suicidal behavior and ideation

Drug Therapy for Epilepsy• Assessment

• History of seizure activity• Allergies and drug history• Knowledge of disease process• Knowledge of drug therapy• Patient lifestyle

Drug Therapy for Epilepsy (cont'd)• Nursing Diagnoses

• Low Self-Esteem (situational or chronic; related to disease effects)• Impaired Social Interaction (related to disease, lack of seizure

control)• Deficient Knowledge (drug therapy)•

Risk for Injury (related to seizures or adverse drug effects)

Drug Therapy for Epilepsy (cont'd)• Planning

• Experience therapeutic effects dependent on the reason the drug is given

• Be free from, or experience minimal, adverse effects.• Understanding of disease and drug regimen and purpose• Understanding of drug regimen• Demonstrate proper self-administration

Drug Therapy for Epilepsy (cont'd)• Implementation

• Monitoring neurological status• Ensuring lab values in normal range• Patient/family teaching about disease • Patient/family teaching about drugs• Patient/family teaching about care during seizure activity

Drug Therapy for Epilepsy (cont'd)• Evaluation

• Effectiveness of drug therapy• Patient goals

Nursing Process Focus: Patients Receiving Antiseizure Drug Therapy






Documents

Drugs for Seizures Chapter 15 15. Antidepressant / Anxiolytic Antidepressant / Anxiolytic escitalopram (Lexapro) Tri-Cyclic Antidepressa nt MAOIs Benzodiazepines