Epilepsy & Pharmacology References: Lilley Pharmacology & Copyright © 2014 by Mosby, an imprint of Elsevier Inc.

History of Epilepsy  Epilepsy was one of the first brain disorders to be described in history  It was mentioned in ancient Babylon more than 3,000 years ago  Through the ages, the strange behavior caused by some seizures has led to the creation of numerous superstitions and prejudices  The term epilepsy is derived from the Greek word epilam- banein, meaning to attack or seize.  People once thought that epileptic individuals were being visited by demons or gods. However, in 400 B. C., the early physician Hippocrates suggested that epilepsy was a disorder of the brain—and he was right. Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 2

Epilepsy Manifestations  Seizures can last from a few seconds to a few minutes…what is an exception?  Patients and health care professionals do not always recognize the signs or symptoms, which can include convulsions, a loss of consciousness, blank staring, lip smacking, or jerking movements of the arms and legs  A seizure has a clear beginning, middle, and end. Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 3

 Seizure  Brief episode of abnormal electrical activity in nerve cells of the brain  Convulsion  Involuntary spasmodic contractions of any or all voluntary muscles throughout the body, including skeletal, facial, and ocular muscles  Epilepsy  Chronic, recurrent pattern of seizures Epilepsy Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 4

 Primary (idiopathic)  Cause cannot be determined  Roughly 50% of epilepsy cases  Secondary (symptomatic)  Distinct cause is identified  Trauma, infection, cerebrovascular disorder Epilepsy (cont’d) Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 5

Diagnosis  Any patient who has a possible seizure disorder should undergo EEG evaluation as soon as possible  Almost all patients with new-onset seizures should have a brain imaging study to detect any underlying structural abnormalities  MRI is superior to CT for detecting cerebral lesions associated with epilepsy Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 6

Seizure Types  Partial (focal) seizures  Simple partial (with motor, sensory, autonomic, or psychic signs; consciousness is not impaired)  Complex partial (consciousness is impaired)  Partial seizures evolving to secondarily generalized seizures  Primarily generalized seizures  Myoclonic  Clonic  Tonic  Tonic–clonic (grand mal)  Atonic  Absence seizure (petite mal)  Unclassified seizures  Neonatal seizures  Infantile spasms Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 7

Partial Seizures  Partial. Partial seizures are confined to discrete areas of the cerebral cortex; only a certain area of the body is usually involved, at least at the start. 5 By contrast, generalized seizures are noted in diffuse regions of the brain. 5  Simple partial seizures cause motor, sensory, autonomic, or psychic symptoms without an obvious alteration in consciousness. These seizures may also be manifested as changes in somatic sensation (e.g., paresthesias or tingling), vision, equilibrium, autonomic function olfactory changes, and hearing. Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 8

Partial Seizures Continued  Complex partial seizures are characterized by focal seizure activity, accompanied by transient impairment of the patient’s ability to maintain normal contact with the environment  Partial seizures can spread to involve both cerebral hemispheres and may produce a generalized seizure, usually of tonic–clonic variety. Secondary generalization is often observed following simple partial seizures, especially those with a focus in the frontal lobe. Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 9

Generalized & Absence Seizures  Generalized. Generalized seizures arise from both cerebral hemispheres simultaneously  Absence seizures (petit mal) are characterized by sudden, brief lapses of consciousness without loss of postural control.  The absence seizure typically lasts for only seconds; consciousness returns as suddenly as it was lost, and there is no postictal confusion. Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 10

Observation of a Tonic-Clonic Seizure  Tonic seizures  During a tonic seizure, the person’s muscles initially stiffen and they lose consciousness. The person’s eyes roll back into their head as the muscles (including those in the chest, arms and legs) contract and the back arches. As the chest muscles tighten, it becomes harder for the person to breathe – the lips and face may take on a bluish hue, and the person may begin to make gargling noises.  Many observers have the misconception that the person is in danger of “swallowing their tongue,” so they attempt to put something in the person’s mouth. Swallowing your tongue is actually impossible, and any attempt to open the now tightly clenched jaw may cause more harm than good.  Clonic seizures  During a clonic seizure, the individual’s muscles begin to spasm and jerk. The elbows, legs and head will flex, and then relax rapidly at first, but the frequency of the spasms will gradually subside until they cease altogether. As the jerking stops, it is common for the person to let out a deep sigh, after which normal breathing resumes.  Tonic-clonic (grand mal) seizures  A tonic seizure is typically accompanied by a clonic seizure – it is rare to experience one without the other. When both are experienced at the same time, this is known as a tonic-clonic 11

 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 Antiepileptic Drugs (AEDs) Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 12

 Single-drug therapy is usually started before multiple-drug therapy is tried  Serum drug concentrations must be measured  Therapeutic drug monitoring  Patients who are seizure free for 1 to 2 years may be able to discontinue antiepileptic therapy Antiepileptic Drugs (cont’d) Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 13

 Exact mechanism of action is not known  Pharmacologic effects:  Reduce nerve’s ability to be stimulated  Suppress transmission of impulses from one nerve to the next  Decrease speed of nerve impulse conduction within a neuron Mechanism of Action and Drug Effects Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 14

 Prevention or control of seizure activity  Long-term maintenance therapy for chronic, recurring seizures  Acute treatment of convulsions and status epilepticus  Other uses Antiepileptic Drugs: Indications Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 15

 Numerous adverse effects—vary per drug  Adverse effects often necessitate a change in medication  Black box warning as of 2008  Suicidal thoughts and behavior  Long-term therapy with phenytoin (Dilantin) may cause gingival hyperplasia, acne, hirsutism  Dilantin facies (if taken during pregnancy- baby may develop short nose, flat face, large head). Antiepileptic Drugs: Adverse Effects Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 16

Classroom Response Question A patient in a long-term care facility has a new order for carbamazepine (Tegretol) for seizure management. The nurse monitors for auto- induction-enzymes formed that lower drug concentration) which will result in A.toxic levels of carbamazepine (Tegretol). B.lower than expected drug levels. C.gingival hyperplasia. D.cessation of seizure activity. Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 17

 carbamazepine (Tegretol)  phenobarbital  phenytoin (Dilantin)  primidone (Mysoline)  valproic acid A Few First-Line Antiepileptic Drugs Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 18

Second-Line Antiepileptic Drugs (Adjunct or supplemental)  ethosuximide (Zarontin)  gabapentin (Neurontin)  lamotrigine (Lamictal)  diazepam (Valium)  clonazepam (Klonopin)  clorazepate (Tranxene)  acetazolamide (Diamox)  levetiracetam (Keppra)  topiramate (Topamax)  zonisamide (Zonegran)  tiagabine (Gabitril)  pregabalin (Lyrica) Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 19

Medications  Both new and earlier AEDs are generally equally effective in new-onset epilepsy  Newer drugs tend to have fewer adverse effects  Patients with newly diagnosed epilepsy can begin treatment with a standard AED (carbamazepine, phenytoin, valproic acid/divalproex, phenobarbital) or with a newer agent (gabapentin, lamotrigine, oxcarbazepine, topiramate)  The choice depends on each patient’s characteristics 20

Classroom Response Question The nurse is assessing the current medication list of a newly admitted patient. The drug gabapentin (Neurontin) is listed, but the patient states that he does not have any problems with seizures. The nurse suspects that the patient A.is unaware of his own disease history. B.has been taking his wife’s medication by mistake. C.may be taking this drug for neuropathic pain. D.is reluctant to admit to having a seizure disorder. Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 21

 Assessment  Health history, including current medications  Drug allergies  Liver function studies, CBC  Baseline vital signs  Seizure precautions Nursing Implications Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 22

Classroom Response Question Before a patient is to receive phenytoin (Dilantin), the nurse practitioner orders lab work. Which lab result is of greatest concern? A.High white blood cell count B.Low serum albumin levels C.Low platelet levels D.High hemoglobin levels Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 23

 Oral drugs  Take regularly, same time each day  Take with meals to reduce GI upset  Do not crush, chew, or open extended-release forms  If patient is NPO for a procedure, contact prescriber regarding dosage Nursing Implications (cont’d) Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 24

Classroom Response Question A patient with unstable epilepsy is receiving IV doses of phenytoin (Dilantin). The latest drug level is 12 mcg/mL. Which administration technique will the nurse use? A.Administer the drug by rapid IV push B.Infuse slowly, not exceeding 50 mg/min C.Mix the medication with dextrose solution D.Administer via continuous infusion Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 25

 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 (Dilantin) Nursing Implications phenytoin (cont’d) Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 26

 Teach patients to keep a journal to monitor:  Response to med(s)  Seizure occurrence and descriptions  Adverse effects  Instruct patients to wear a medical alert tag or ID  Anti-epileptic drugs should not be discontinued abruptly  Follow driving recommendations Nursing Implications (cont’d) Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 27

 Teach patients that therapy is long term and possibly lifelong (not a cure)  Monitor for therapeutic effects  Decreased or absent seizure activity  Monitor for adverse effects  Mental status changes, mood changes, changes in level of consciousness or sensorium  Eye problems, visual disorders  Sore throat, fever, blood dyscrasia may occur (imbalance of components in blood)  Many other adverse effects especially with other meds Nursing Implications (cont’d) Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 28

Classroom Response Question Which information will the nurse provide to the patient who is receiving antiepileptic drug therapy? A.If you feel sleepy when taking the drug, decrease the dose by one half B.Take the drug on an empty stomach C.Call your health care provider if you experience a sore throat or fever D.Patients with epilepsy are not able to hold a job and work, so you should apply for benefits Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 29

Aura is the term used to describe symptoms that may occur before a seizure and may include:  Visual changes. Examples include:  Bright lights.  Zigzag lines.  Slowly spreading spots.  Distortions in the size or shape of objects.  Blind or dark spots in the field of vision  Hearing voices or sounds (auditory hallucinations)  Strange smells (olfactory hallucinations).  Feelings of numbness or tingling on one side of your face or body.  Feeling separated from your body.  Anxiety or fear.  Nausea 30

Case Scenario Patient 31

Patient Has a History of Epilepsy: Refer to progress notes, co-workers observed seizure at work and called Admit to medical-surgical unit 2.Code status: Full code 3.Continuous cardiac monitoring and pulse oximetry, maintain 02 sat >94% 4.Neurologic assessment and vital signs every 2 hours 5.Seizure precautions 6.Up as tolerated with assistance only 7.Start saline lock 8.Regular diet 9. Tegretol 200 mg by mouth 3 times per day 11. Complete blood cell count, magnesium, and basic metabolic panel STAT 12. Valproic Acid level STAT 13. Call provider with laboratory values 14. For seizure activity, administer lorazepam 2 mg IV STAT, may repeat dose once if initial dose is ineffective; notify provider 15. Give loading dose of fosphenytoin IV 15 mg/kg at a rate of no more than 150 mg/minute Copyright © 2014 by Mosby, an imprint of Elsevier Inc. 32