Fitzy Pharm Seizures And Epilepsy Flashcards
What drugs will treat absence seizures?
Ethosuxamide and valproic acid
Myoclonic clinic seizures
Benzodiazepines, clonazepam
Tonic clinic seizures
Narrow spectrum drugs: phenytoin and phenobarbital
Simple and complex seizures
Gabapentin, pregabalin, oxcarbamazepine, lacosamide, tiagabin, visabatrin, exogamous
Tonic clonic partial onset seizures
Narrow spectrum drugs: carbamazepine, phenytoin, phenobarbital
*cbz is only with partial onset seizures
What are the broad spectrum AED’s?
The treat generalized or partial onset seizures: Very low table lacks zest
- valproic acid
- lamotrigine
- topic image
- levetiracetam,
- zonisamide.
Which AED’s will prolong the fast inactivation state of Na channels?
Lamotrigine and oxcarbamazepine
Which AED enhances slow inactivation?
Lacosamide
*important because of different mechanism
Which AED is slightly lipophilic?
Lamotrigine
* it just kinda sneaks to that internal binding site so it’s not as use-dependent as the other ones
Why do Na channel blockers act preferentially at the sites of epilepsy
They have the highest frequency of being open so the drug can bind to it!
Which drug is more effective in blocking high frequency firing? Phenytoin or carbamazepine?
Carbamazepine
What makes lamotrigine different from phenytoin or carbamazepine?
It also acts on other things like n and p type voltage gated calcium channels in the cortical neurons and neocortical potassium currents
What does lacosamide stabilize?
The slow inactivated state… The one where everything is totally shut
-works best when the stimulus was prolonged for tens of seconds
What kind of channels mediate absence seizures?
T-type calcium channels
*the 3 Hz spike is the dead giveaway
So, what drugs can be used to treat absence seizures?
-antagonists of t-type calcium channels
-narrow spectrum : ETHOSUXAMIDE
It sux because it’s only used for absence seizures and only limits excitation ….. And it’s non-sedating which sux as well
Valproate
- 1st line for generalized onset seizures
- has intolerable adverse effects—- weight gain, hair loss, lethargy
Lamotrigine
Gets the Na v channels like cbz and phenytoin
-BUT it also acts at n and p type calcium channels in cortical neurons and neocortical potassium currents
Zonisamide
- sulfanilamide derivative
- blocks Nav channels and t-type calcium channels
What drugs will enhance the post-synaptic GABAergic neuronal transmission?
- phenobarbital and related barbiturates
- primidone…. Active metabolite is phenobarbital
- benzodiazepines (diazepam and lorazepam and friends)
What are phenobarbital’s complications?
Can cause significant sedation
- lethal respiratory depression
- has abuse and addiction potential
- these suck, so benzodiazepines were made*
How do benzodiazepines work?
Bind to distinct site… Aldosterone potentiation… GABA binds… There ya go….channel opens with greater FREQUENCY
How does phenobarbital work?
Binds to distinct site on GABA receptor,
-increases the duration of the Cl- channel opening
Why is the lethality of phenobarbital so much higher than benzodiazepine?
High douses of barbiturates are GABA independent
What drugs are used to manage status epilepticus?
Diazepam or lorazepam with Fosphenytoin if needed
