Ch. 16/17: Anticonvulsants/Anti-Epileptics and Resp. Stimulants (Vickroy) Flashcards
(47 cards)
When is doxapram contraindicated?
animals with seizure disorders
most common spontaneous neuro disorder in dogs
seizures
Importany questions to ask when dog has seizures
- is the reported event truly a seizure?
- can an underlying cause be identified and treated?
Things that can mimic seizures
- cataplexy/narcolepsy
- vestibular episode
- encephalitis
- exercise-induced collapse
- drug-induced dyskinesias
- cervical m. spasm
- episodic NM dz
- metabolic event
most (90%) of seizures are CNS or non-CNS?
CNS
causes of non-CNS induced seizures
- metabolic/electrolyte imbalance (hypoxia, dec. Glu/Ca/Mg, inc. K)
- liver dz
- renal failure
- drugs/toxins
- hypothyroidism
causes on CNS induced seizures
- organic brain disease (45%) (tumor, infection, head trauma) –> 2ary epilepsies
- idiopathic epilepsy (45%) –>1ary epilepsies
idiopathic epilepsy
poorly char. CNS disorder that manifests as episodes of intermittent high neuronal activity
- usually life-long*
- can be focal or diffuse in brain
- can be initiated by sensory or external stimuli
seizure
a clinical manifestation of excessive and/or hyper-synchronous neuronal discharges in the brain
-may present as episodic impairment or loss of consciousness accompanied by abnormal motor phenomena, psychic or sensory disturbances, ANS signs
convulsion
motor manifestation of seizures that involves involuntary contraction-relaxation of body muscles
epilepsy
commonly defined as 2+ seizures at least 24hrs aparts, resulting from a nontoxic/nonmetabolic cause
status epilepticus
continuous seizure activity lasting 30min or longer. Life-threatening
T/F: prolonged periods of seizure activity can produce irreversible brain damage and neuronal death and are char. by:
- extremely high use of O2 and glucose
- followed by prolonged CNS depression (unconsciousness)
- requires some form of intervention**
anti-epileptic agent curative of seizures?
NO. Only reduces the symptoms
2 general mechs. by which anti-epileptics act:
1) suppress initiation of neuronal firing in epileptiform foci
2) inhibit spread of seizure activity into normal tissues
disadvantages of AEDs
- high percentage of animals are refractory to AEDs
- high incidence of side effects
- devel. tolerance
- loss of clinical efficacy over time
empirical use
to use what works in the patient as long as it works and is tolerated by the patient and o
phenobarb fx
- long-acting barbiturate w/ anti-seizure properties
- sedative
barbiturates are classified according to:
duration of action
phenobarb mech. of action
facilitates GABA activation of GABA-A receptor and opening of Cl channels –> CNS depression (i.e. cortical motor centers)
all barbiturates are acids/bases
acids
T/F: phenobarb is DEA-controlled drug**
T. (class 4 agent)
common side effect when starting phenobarb tx of seizures
sedation (however, tolerance to this builds up over time)
long-term use of what two classes of drugs causes physical dependence?**
opiates, barbiturates. Severe withdrawal symptoms can result!
