Anticonvulsants Flashcards
What is epilepsy?
Seizure disorder of sudden discharge of cerebral neurons
- Caused by electrical activity in the brain; recorded with EEG
- “seizure” - episode of neurologic dysfunction, often accompanied by motor activity such as convulsions, and emotional/sensory change
- May include visual, auditory or olfactory hallucinations
T or F, epilepsy is a multifactorial disease
True, etiologies may include: infection, trauma, neoplasms, fevers, genetic/birth influences, hereditary factors, etc.
Majority of patients with epilepsy have what?
idiopatchi epilepsy = no known cause
Drugs for epilepsy provide marked improvement in what percentage of patients?
70-80%
2 broad groups of epilepsy:
- Partial epilepsies (Most common type)
2. Generalized epilepsies
Two subtypes of partial epilepsy
- Simple partial
2. Complex partial
Describe simple partial epilepsy
Seizures caused by a group of hyperactive neurons confined to a single locus in the brain
Describe the 5 details regarding partial epilepsy
- Electrical disorder does not spread
- Seizure lasts for only a few seconds
- Individual does not lose consciousness
- Often exhibits abnormal activity of a single limb or muscle group
- May occur at any age
Describe what a complex partial epilepsy is
Seizures exhibit complex sensory hallucinations, mental distortion and loss of consciousness
Describe the 2 details to complex partial epilepsy
- Aura (seizure symptoms before it occurs); seizure lasts for 3 to 5 minutes
- Full consciousness is slow to return
Complex partial epilepsy is also known as what?
psychomotor or temporal lobe seizures
80% of people with complex partial epilepsy experience initial seizure prior to what age?
prior to 20 years of age
Name the two types of Generalized Epilepsies
Tonic-clonic (grand mal)
Absence (petit mal)
Consciousness is lost with which type of Generalized Epilepsy?
Both types
Tonic-clonic (grand mal) & Absence (petit mal)
What is the most dramatic form of epilepsy?
Tonic-clonic (grand mal)
Sequence of events during a tonic-clonic
Seizures result in:
- loss of consciousness
- tonic
- clonic (convulsive twitching)
Define tonic and clonic
tonic: producing/restoring normal tone; continuous tension
clonic: contraction/relaxation of muscle
Major motor activity during a tonic-clonic
fall to floor, tonic rigidity, chronic jerking of face and limbs
Tonic-clonic seizure is followed by what?
a period of confusion and exhaustion
- Can become Comatose
- Consciousness returns with confusion, headache, drowsiness
What is an aura?
Brief period of heightened sensory activity prior to the onset of the seizure
- Characterized by numbness, nausea, or unusual sensitivity to light, odor, sound
Define an Absence (petit mal) epilepsy
seizures involve an abrupt and brief loss of consciousness (10-30 seconds)
When does the onset of Absence (petit mal) epilepsies occur?
Onset occurs at 3 to 5 years old and lasts until puberty (disappears in middle adulthood)
CHILDREN!
Describe the aura that occurs in Absence (petit mal) epilepsies
There is no aura; patient stares and has rapid eye blinking for 3 to 5 seconds; quickly returns to normal
What is status epileptics?
Seizures are continuous or rapidly recurrent
- can be life-threatening
What happens if you have a patient that has status epilepticus in the dental office?
give injection of diazepam (valium)
- May also use lorazepam (Ativan) and midazolam (Versed) PARENTERALLY
What are the goals of drug therapy for epilepsy
- to control seizures (frequency)
2. Minimize adverse reactions
Mechanism of drug therapy for epilepsy
prevent the spread of abnormal electric discharges in the brain without causing excessive drowsiness
- CNS depressants
T or F, Epilepsy drugs are usually taken for life
True: chronic toxicity becomes an important consideration when selecting an agent
How big of a therapeutic index do anticonvulsants have?
Narrow therapeutic index
- titrate dose carefully; monitor blood levels
When dosing, need to consider that most anticonvulsants stimulate what?
liver microsomal enzymes (inducers)
- when adding additional anticonvulsants, changes the metabolism of all anticonvulsants
At low doses, how are metabolized anticonvulsants eliminated? Are they always eliminated this way?
FIRST ORDER elimination (drug can be removed from body after metabolism).
-No, After saturation of liver enzymes, metabolism converts to ZERO ORDER KINETICS = blood level increases abruptly
3 common side effects with anticonvulsants
- CNS depression
- CNS depression is addictive with other CNS depressants
- Opioids in dentistry; alochol
- GI effects (can be minimized by taking drug with food)
- prescribe agents that can irritate the GI tract cautiously in patients taking anticonvulsants (NSAIDS)
