Anticonvulsants Flashcards
what are anticonvulsants?
Drugs used to prevent seizure activity
what is a seizure?
periods of altered brain function due to recurrent abnormal electrical impulses
what is epilepsy?
recurrent seizures caused by a brain abnormality
what is a convulsion?
seizure characterized by spastic muscle movement
what is a partial seizure
animal may exhibit spastic muscle contraction in a limb, facial muscles
Grand Mal Seizure– animal unconscious, exhibits spastic muscle contraction over the entire body; salivation, chewing, defecation, urination may occur
Status Epilepticus– a continual seizure
what may an animal experience during a partial seizure? (3)
hallucinations
develop apparent blindness
behavioral abnormalities
what are the phases of seizure?
Preictal phase
Ictal phase
Postictal phase
what is the preictal phase?
before seizure occurs
what may the animal experience during the preictal phase?
pacing, panting, anxiety, apprehension
what happens during the ictal phase?
seizure occurs
how long does the ictal phase last
1 - 2 minutes
what is teh postictal phase?
after seizure subsides
can can the animal experience during the postictal phase
tired, confused, anxious
what can be some cause of a seizure? (7)
- Idiopathic
- Hypoxemia
- Hypoglycemia
- Hypocalcemia
- Toxins
- CNS infections
- CNS tumors
which cause for seizures has no identafiable cause?
Idiopathic
which cause of seizure is due to lack of oxygen?
Hypoxemia
which cause of seizure is due to low blood sugar?
Hypoglycemia
which cause of seizure is due to low calcium?
Hypocalcemia
which anticonvulsant drug is the most popular anticonvulsant drug for long-term control of seizures?
phenobarbital
how is pehnobarbital distributed?
Highly protein bound
which dugs should phenobarbital not be given with?
Aspirin and sulfonamides
where is phenobarbital metabolized?
liver
how does the therapeutic dose vary?
between individuals
what are some common side effect of phenobarbital? (3)
sedation
incoordination
lethargy
waht are some rare side effects of phenobarbital? (2)
liver disease
anemia
what should be monitored while on phenobarbital?
Therapeutic drug concentration
which anticonvulsant drug is commonly used in conjunction w/ phenobarbital to control seizures?
potassium bromide
which anticonvulsant has a narrow therapeutic index?
potassium bromide
why does potassium bromide have a narrow therapeutic index?
Concentration for control is very close to the toxic level
what can be seen with potassium bromide toxicity? (2)
GI irritation
sedation seen
how is potassium bromide eliminated?
kidney
what form is potassium bromide avaiable in?
Available as a powder that is mixed w/ dextrose or corn syrup for oral administration
what should be monitored while on potassium bromide?
Loading dose and therapeutic drug concentration
what is the drug of choice for emergency treatment of convulsing animals?
Diazepam
what route of administration is diazepam given to produce effective results?
intravenously
how is diazepam metabolized by the liver?
rapidly
how long is the duration of diazepam?
Short
what is the effect like when giving diazepam orally?
Poor
what can diazepam be used to help treat in cats? (3)
- appetite stimulant
- urine marking
- anxiety
what anticonvulsant can be used on dogs (cats) when phenobarbital and/or potassium bromide aren’t controlling seizures adequately?
Levetiracetam (Keppra)
what anticonvulsant is used on dogs with refractory seizure activity?
Zonisamide
what is primidone metabolized into by the liver?
phenobarbital
which anticonvulsant is a human drug, seldom used in animals?
Phenytoin
how is phenytoin absorbed?
Poorly from GI tract
how is phenytoin metabolized?
quickly
what is a possible concern with taking phenytoin?
Hepatoxicity
what does doxapram do?
Stimulates the respiratory center in the brainstem
when is doxapran used?
Used to counteract apnea, slow breathing
what medical consideration should doxapram not be used?
animals prone to seizures
