Okay. In this video, we are going to recover the remaining nervous system medications. If you are
following along with cards, I am on card 86 in our Pharmacology Flashcards, edition 2.
In this video, we will be covering antiseizure medications, medications for insomnia,
as well as sedative hypnotic medications, and then general anesthetic agents as well.
Alright. Let's talk about antiseizure medications. There are many antiseizure medications out there.
I've chosen 4 of what I feel like are the most common and more important
ones to know, to include here on card 86. So those are phenytoin as well as topiramate,
levetiracetam, and primidone. So let's go through some of the common side effects
as well as key points regarding administration of these medications.
For phenytoin, a key side effect that you definitely have to know is gingival
hyperplasia. So that is basically an overgrowth of gum tissue. The gums become enlarged. Other side
effects include vision issues, dizziness, GI upset, as well as a possible rash.
So when a patient is on phenytoin, we are going to need them to come in for frequent blood draws
because the therapeutic range for phenytoin is pretty narrow and it's hard to hit it just
right with the dose. We don't want to be too high because we'll have toxicity, and we don't want to
be too low because it won't be effective. So we're going to need those blood draws
pretty frequently to get the dose just right. We want the level to be between 10 and 20 μ/mL.
Then, with topiramate, topiramate can cause side effects such as vision issues, dizziness,
and sedation, as well as metabolic acidosis. Because of that side effect of metabolic
acidosis, we're going to want to monitor the patient's bicarbonate levels during therapy.
Then with levetiracetam, this can cause behavioral abnormalities, as well as fatigue
and agranulocytosis. So agranulocytosis means it basically causes white blood cell counts to
drop, which in turn places the patient at high risk for infection.
So we're definitely going to want to monitor the patient's CBC levels and
monitor them for signs of infection. And then lastly, with primidone. Primidone
has side effects such as drowsiness, GI upset, as well as blood dyscrasias.
So with Primidone, this actually has a very narrow therapeutic range as well, just like
we had with phenytoin. So again, our patient is going to have to go get frequent blood draws to
make sure our dose is just right and within the proper range, which is between 5 and 12 μ/mL.
Alright. Now let's talk about medications that are used for insomnia. Medications that fall
within this class include zolpidem, which is Ambien, and eszopiclone, which is Lunesta.
These medications both work by increasing GABA in the central nervous system,
which helps to promote sedation and sleep. So the way I remember these medications is
that they both contain Zs. So zolpidem and eszopiclone can help you catch some Zs.
Side effects with both of these medications include daytime sleepiness, which is very common,
as well as dizziness, and then possible abnormal thinking and behavior.
So these medications actually carry a black box warning because of the
possibility for abnormal thinking and behavior. So some patient teaching you will want to do,
you really want your patient to allow for at least 8 hours for sleep each night.
Also melatonin is another supplement that can be used to help regulate the
sleep-wake cycle and may be effective for the patient as well who is dealing with insomnia.
Alright. Now let's talk about barbiturates. Barbiturates are sedative hypnotic agents.
And the key medication to know within this class is pentobarbital.
Pentobarbital can be used for preoperative sedation as well as in the treatment of
seizures. It can also help to induce a coma in a patient who has high intracranial pressure.
It works by increasing GABA, which results in central nervous system depression.
Side effects include lethargy, hypotension, respiratory depression, as well as constipation.
The way I remember this medication is that, "I climbed over some barbed wire to get into the
Pentagon, and the Secret Service came and knocked me out with some pentobarbital and took me to
jail." So obviously it didn't happen, but that's my little story on how I remember pentobarbital.
So if your patient is on pentobarbital, you definitely want to closely monitor their vital
signs, and you want to make sure that there is resuscitation equipment available at the beside.
Alright. The last nervous system medication that I'm going to go over is a general anesthetic agent
which is propofol. Some of you may remember propofol because Michael Jackson used that
in conjunction with some benzodiazepines, and that resulted in his death.
Propofol is used in the induction and maintenance of general anesthesia.
It also provides sedation for intubated patients. The mode of action of propofol is to potentiate
the effect of GABA, and it results in side effects such as amnesia,
bradycardia, hypotension, and respiratory depression. So it brings everything down.
When you are administering propofol to your patient, you're going to want to continuously
monitor their vital signs. Also keep in mind that propofol does not treat pain, right? It has no
analgesic effect. And then the other thing you need to keep in mind is that you need to use
unused portions of propofol within 6 hours because of the risk of bacterial contamination
with this medicine. My way of remembering
propofol, it starts with that P-R-O-P like prop. So if you are given propofol, someone will have
to prop you up because you will be knocked out. So hopefully that's helpful for you.
That wraps up our nervous system medications. And in my next video,
we will start in on musculoskeletal medications. Thanks so much for watching!