Epilepsy Flashcards
A finite clinical manifestation of abnormal and excessive excitation of a population of cortical neurons is called a?
Seizure
A syndrome characterized by chronic, recurrent seizures unprovoked by systemic neurologic insults is called?
Epilepsy
*Epileptogenesis is the sequence of events that converts normal neuron network into hyperexcitable
Metabolic/electrolyte imbalance, intoxication, sedatives/ethanol, sleep deprivation, reduction in treatment, hormonal variation, stress, hypoxia, fever/infection and concussion are all common what?
Seizure precipitants
What are the two main classes of seizures?
1-Partial seizures
2-Generalized seizures
What are the 3 types of partial seizures?
1-Simpe partial (aware and responsive, focal)
2-Complex partial (initially aware, focal with minor spread
3-Secondarily generalized (initially aware, then loss of responsiveness as seizure generalizes)
Characterized by loss of awareness and responsiveness generalized from onset, what are the 3 types of Generalized Seizures?
1-Tonic-clonic (T=stiff, C=jerking, AKA grand mal)
2-Absence (Petit mal)
3-Atonic (drop)
Which type of seizure is focal, and has normal awareness, memory and consciousness throughout seizure?
Simple Partial Seizures
*Shortest duration (60-90 sec), motor and somatosensory
Which type of seizure has localized onset and spreads, and has awareness that may be impaired as it progresses?
Complex Partial Seizure
*15-120 sec
Which type of seizure begins as simple and/or complex partial seizures but fully generalize with Tonic and Clonic phases?
Secondarily Generalized Seizures
*30-240 sec, has Postictal phase of confusion and somnolence
Which type of seizure is characterized as a vacant stare that may appear as a loss of attention?
Generalized Absence Seizure
Which type of seizure is generalized from onset and involves stiffening and jerking?
Generalized Tonic-Clonic Seizure
*Often lethargic and confused after and wants to sleep
What is the main problem of ASDs that are available?
They treat symptoms and 1/3 of patients are refractory to all treatments available
What are the 3 main mechanisms for ASDs?
1-Enhancement of GABA-mediated inhibition
2-Reduction of excitatory transmission
3-Modification of ionic conductance
What are the 5 main drugs used to treat epilepsy?
1-Carbamazepine 2-Phenytoin 3-Topiramate 4-Valproate 5-Ethosuximide
Which ASD is indicated for simple and complex Partial and generalized tonic-clonic seizures and is associated with Stevens Johnson syndrome?
Carbamazepine
*Avoid in absence patients (may aggravate) High drug-drug interaction rate
What is the Mechanism of Action of Carbamazepine?
Blocks use-dependent voltage gated Na channels to inhibit repetitive firing. similar to Phenytoin
Which syndrome is a mild form of toxic epidermal necrolysis that results in painful lesions of the mucous membranes?
Stevens-Johnson Syndrome
*Slow acetylators, immunocompromised, sodium channel blockers and radiotherapy patients at higher risk
What type of juice blocks CYP3A4 resulting in increased plasma levels of carbamazepine?
Grapefruit juice
Which ASD is indicated for uncomplicated absence seizures only and has a 40 hour half-life?
Ethosuximide
*minor weight loss. reduces T-type Ca channel currents
Which ASD is indicated in Simple and complex partial and generalized tonic-clonic seizures, causes gingival hyperplasia and has zero-order kinetics at high doses?
Phenytoin
*not recommended for absence patients. blocks Na channel
Which ASD is indicated in simple and complex partial generalized tonic-clonic, and lennox-gastaut syndrome as is associated with weight loss and word recall problems?
Topiramate
*increases metabolism of estrogen thus affecting birth control
What is the mechanisms of action of Topiramate?
Broad Specturm- Blocks Na channels, inhibits Ca currentsf, AMPA/Kainate receptors and potentiats GABA currents
Which ASD is indicated for generalized complicated absence, atypical absence, myoclonic tonic clonic and simple and complex partial seizures and is associated with weight gain and Reye-like syndrome?
Valproic acid
*contraindication for hepatic disease. increased neural tube defects
What is the mechanisms of action of Valproic Acid?
Broad spectrum- blocks VGSC, reduces NMDA currents, Increases GABA-mediated Cl currents
A category D risk, which drug is associated with Spina bifida and other birth defects?
Valproate
Which three drugs are indicated for Partial seizures?
1-Carbamazepine
2-Phenytoin
3-Topiramate (if secondarily generalized)
Which two drugs are indicated for generalized onset tonic clonic seizures?
1-Valproate
2-Topiramate
Which two drugs are indicated for absence seizures?
1-Ethosuxmide (Uncomplicated)
2-Valproate (Complicated)
What are 5 important dental considerations for those with Epilepsy?
1-Increased decay
2-Increase fracture risk due to vitamin D deficiency
3-Gingical Hyperplasia
4-Impaired wound healing/prolong bleeding
5-Increase drug interactions
