Antiepileptics - session 22 Flashcards
What is the most common cause of recurrent seizures in dogs?
Idiopathic epilepsy
What is the most common cause of seizures in cats?
intracranial
If a dog/cat presents with cluster seizures. There is no history of seizures previously. What class of seizures should you consider?
intracranial
How is phenobarbital metabolized?
Liver
List the most common persistent AE associated with Phenobarbital
PU/PD
polyphagia
What steps should be taken when rapid elevation of ALT is noted in a dog taking phenobarbital?
Stop PB immediately, switch to alternative anti-epileptic drug
What AED is a risk factor for superficial necrolytic dermatitis in dogs?
Phenobarbital
Clinical signs of anprexia, sedation, ascites, and icterus are associated with what process?
Hepatotoxicity
At what frequency should animals receiving chronic PB therapy be evaluated?
every 6 months
What is a risk of administering Phenobarbital with a tetracycline?
P450 inhibitors can inhibit hepatic metabolism causing inc in serum conc and PB toxicity
P450 drugs: Chloramphenicol, tetracyclines, cimetidine, ranitidine, enilconazole
What drugs are P450 inhibitors?
H2 blockers:
- cimetidine
- ranitidine
antibiotics:
- chloramphenicol
- fluoroquinolones (enrofloxacin, marbofloxacin)
azole antifungals:
- ketoconazole
- enilconazole
What is the initial AED of choice in dogs with hepatic dysfunction?
potassium bromide
What AE does Potassium bromide have in cats that makes it contraindicated?
Fatal Progressive bronchitis
What are the dietary Chloride requirements when on KBr?
Keep normal Cl
What adverse effects are associated with KBr?
PU/PD, polyphagia - less dramatic then with PB
Which AED does not cause sedation?
Felbamate
Which AEDs are a structural analog in GABA?
Gabapentin, Pregabalin
Which AED can cause KCS?
Felbamate
Which AED do patients rapidly develop tolerance to anticonvulsant effects?
Diazepam
What is the preferred choice for chronic AED therapy in cats?
Phenobarbital
Diazepam = hepatotoxicity
What AED’s are metabolized by the liver?
Phenobarbital Zonisamide Diazepam Gabapentin (minor) Felbamate
Which AED is associated with dec tear production?
Zonisamide
Which AED is contraindicated in cats due to its association with potentially fatal drug-induced bronchitis?
Potassium Bromide
Which anti-epileptic drug can be used as an at-home, rectally administered emergency treatment for cluster seizures?
Diazepam
What is the criteria for starting an antiepileptic?
- 3+ seizures in 24 hr
- seizures >5min
- 2+ seizures in 6 months
- protracted severe or unusual
What AED is recommended as a second line AED with little evidence supporting its use as monotherapy?
Levetiracetam
What AED’s can be used as monotherapy?
Phenobarbital, Potassium Bromide
Which AED causes acute fatal hepatic necrosis when administered orally to cats?
Diazepam
What 2 drugs have significant side effects in cats?
Potassium bromide - allergic bronchitis
Diazepam - hepatic necrosis
In dogs and cats, what is the most effective antiepileptic drug?
Phenobarbital
What class of AEDs is recommended as first line therapy to stop seizure activity with status epilepticus?
Benzodiazapines (Midazolam)
What is the goal of emergent anticonvulsant therapy?
stop all seizure activity immediately and prevent additional seizures for 24hr period
Which Benzodiazepine can be given IM?
Midazolam
