Treatment of epilepsy Flashcards
Epilepsy is not a diagnosis itself and the underlying cause needs treating. What are you aiming to do when treating epilepsy?
Reduce frequency and severity of seizures
Minimise side effects
Maximise quality of life
How dos the number of epileptic foci affect treatment success?
More epileptic foci - less successful treatment with AED
What is defined as an animal being responsive to AED treatment?
50% or more reduction in seizure activity
Many human drugs can’t be used for AEDs as they are ineffective or unsafe. What are the 3 broad categories of AEDs? (Ideally use a single agent, but many drugs require more than 1 AED)
Drugs which enhance GABA action
Drugs which suppress glutamate action
Drugs which modulate cation movement
Give examples of 3 AEDs
Potassium bromide
Phenobarbital
Imepitoin
How does potassium bromide work as an AED
Enhances GABA
How does phenobarbital work as an AED?
Enhances GABA
Inhibits glutamate
Reduces current through voltage gated calcium channels
How does imepitoin work as an AED?
Enhances GABA
Reduces current through voltage gated calcium channels
How are AEDs administered?
Phenobarbital - oral or IV
Potassium bromide - oral
Impeitoin - oral
Phenobarbital is highly protein bound. Where is it metabolised and excreted?
Metabolised in liver
Excreted unchanged in urine
What are adverse effects of phenobarbital?
Metabolism in liver causes auto induction of CP450
Potentially hepatotoxic
What is an adverse effect of potassium bromide?
Causes gastric irritation
Where is potassium bromide excreted? What do you need to be careful with?
Kidneys
Competes with chloride - careful with salt intake
Which species should not be given potassium bromide? Why?
Cats - irreversible allergic pneumonitis
Where is imepitoin metabolised and excreted?
Metabolised - liver
Excreted - unchanged in faeces
