February 1, 2023

This is a brief summary of anticonvulsants, or medicines used to treat epilepsy.

This is a short review of anticonvulsants or medicines used to treat epilepsy to treat people that have seizures kind of categorize the anticonvulsant here into a few categories up top in the red are the sodium channel blockers next is a calcium channel blocker after that in green is a gaba antagonist next are two drugs that have many mechanisms of actions some of

Which are listed above and lastly the last three in a purpley pink color have unknown or not well understood mechanisms of actions let’s talk about the first one in the list carbamazepine mechanism of action for carbamazepine is that it is a sodium channel blocker it specifically binds inactive sodium channels to extend their inactivation which prevents the random

Firing in the brain that causes seizures based on the modern approach of treating epilepsy this drug carbamazepine should be used for simple partial complex partial and secondary generalized seizures it’s considered narrow spectrum other indications for carbamazepine are trigeminal neuralgia bipolar disorder so it can be used to treat epilepsy trigeminal neuralgia and

Bipolar disorder now for the side effects i’ve listed the main and notable side effects first main side effect for carbamazepine is hyponatremia which kind of makes sense because it blocks the sodium receptor some of the other side effects which are included in many of the other drugs on this list are bone marrow suppression hepatic toxicity sedation dizziness nausea

Vomiting double vision ataxia fetal malformations bone demineralization and stevens-johnson syndrome which is a nasty rash carbamazepine interacts with p450 enzymes and it actually induces p450 enzymes which can reduce the efficacy of other drugs that use this that use this metabolism system and because it interacts with a p450 system its metabolism is is obviously

Hepatic next time’ list is another sodium channel blocker phenytoin this is complex actions but essentially blocks sodium channels also used for the same kinds of seizures simple partial complex partial and secondary generalized no other indications for phenytoin the main side effects here are bone demineralization gingival hyperplasia which follows long-term use

Of phenytoin hypotension arrhythmias and tissue necrosis which follows iv administration of phenytoin we see the same list of side effects here bone marrow suppression patent toxicities sedation dizziness nausea vomiting that same list kind of applies to many of the anticonvulsant phenytoin also induces the p450 enzymes and s metabolism is hepatic the mantra gene

Is the last of the sodium channel blockers it’s specifically selective for excitatory neuron niraj neurons with excitatory neurotransmitters such as glutamate so neurons that use glutamate might be blocked by lamont regine it’s used to treat all seizures as considered a broad spectrum anticonvulsant other indications are bipolar disorder and antidepressant effects

Main side effect for lamont rajan is steven johnson syndrome which is that which is that nasty rash can be life-threatening and it has the same list of side effects as the others this drug interacts with p450 enzymes it doesn’t necessarily induce p450 enzymes it doesn’t make them work more efficiently however oral contraceptive pills can decrease the efficiency

Of l’immagine so both of those interactions are worth knowing and there is hepatic metabolism for the mod regime next is ethos xm id which is a calcium channel blocker specifically the alpha subunit of t-type calcium channels in the thalmic neurons this is specifically used for absence seizures so it’s also considered a narrow spectrum because it’s only used for

That one kind of generalized seizure the sauce seizure there are no other indications but it is first-line for absence seizures ether sucks amide that so that’s worth emphasizing no notable side-effects here just the same as the rest no notable interactions either and addition patek metabolism phenobarbital is next this is a gaba antagonist it augments the gaba

Receptor which as in anticonvulsant effect because gaba is a is an inhibitory neurotransmitter it specifically augments the calcium excuse me the chloride channel that that is a gaba receptor this is also narrow spectrum so it’s used to treat simple partial complex partial and secondary generalized seizures it’s also used for tremors similar to a drug called

Primidone which is used for a central tremor main side effects of phenobarbital are hyperactivity addiction and sedation those kind of makes sense because it is a barbiturate phenobarbital causes hyperactivity addiction and sedation same list of other notable side effects there this is another p450 inducer and it’s also metabolized hepatic li next is valproate

Which has many mechanisms of actions including blocking sodium channels enhancing gaba and blocking calcium channels it’s used for all seizure types considered broad spectrum also used as migraine prophylaxis and also used for bipolar disorder main side effect here are that it causes fetal malformation it’s a strong teratogen can also cause weight gain tremors

Hair loss fulminant hepatic failure which limits its use of kids and bone marrow suppression and the rest of the side effects as usual it’s a p450 inhibitor which has the opposite effect of phenobarbital phenytoin and carbamazepine and it’s also had pratically metabolized next is topiramate which also has many mechanisms of actions this time it blocks sodium it

Enhances gaba and it blocks a glutamate receptor specifically the nmda receptor also broad-spectrum anticonvulsant it treats all seizure types it’s also used for migraine prophylaxis so there are some similarities between the valproate and topiramate main side effects of topiramate are cognitive impairment weight loss and kidney stones and the rest of the side

Effects as usual topiramate specifically interacts with oral contraceptives this time topiramate decreases the efficacy of oral contraceptives as opposed to the kind of the flipped effect of oral contraceptives decreasing the efficacy of lamotte regime this has both a paddock and renal metabolism in about a 7230 ratio next on the list is gabapentin has an unknown

Or partial mechanism it’s used to treat narrow a narrow spectrum of seizure types of epilepsy it’s also used to treat neuropathic pain and chronic pain main side effects here are ankle edema and weight gain along with the rest of the usual and it interacts with antacids its renal metabolism here this one is full renal metabolism per gabilan is similar to gabapentin

Has an unknown or not well understood mechanism narrow-spectrum used to treat neuropathic pain this time neuro or this time fibromyalgia side effects are similar the notable ones are ankle edema and weight gain along with the rest of big interaction with antacids which limit the availability of pregabalin and it’s also readily metabolized so gabapentin and pre

Gabilan are pretty similar gabapentin is used to treat chronic pain / gavilan is used to treat fibromyalgia but they both cause pinkel edema weight gain can’t be used with antacids arenal ii metabolized or narrow-spectrum anticonvulsant and have mechanisms that aren’t really well understood last on the list is legato acetate which also has an unknown mechanism it’s

Used to treat all seizure types it has no other indications main side effects here are depression and behavioral and psychiatric issues which can be found in up to ten to fifteen percent of people who use this drug know main interactions here and its metabolism is renal this has been a review of anticonvulsant medications i hope this was helpful thank you for listening

Transcribed from video
Anticonvulsants (antiepileptic drugs) By MedLecturesMadeEasy