Okay, now Methylxanthines.
I told you that we used to use this a lot
more but we don't really use this as much
but they're still out there,
so you need to know it.
It causes bronchodilation by
relaxing the smooth muscle
but it also causes some pretty
significant CNS excitation,
it can also make you urinate a lot, diuresis, pulls
off a lot of fluid and you have vasodilation.
So, here's a lot of different options
that go along with this.
That's different than a LABA or a SABA because
it's not hitting the beta-2 adrenergic agonist,
that's not how the
So usually there is an oral
dose but it also can be give IV
but we have to do a lot of monitoring
for these types of medications
and they're not as effective
as beta-2 agonists.
Now they will last longer, Methylxanthines
will last longer than beta 2 agonist
but they've got those drawbacks.
You end up with the patient having this diuresis
which may or may not be something we want.
They have more significant CNS excitation
and they're just not as effective.
That narrow therapeutic window, that means that
in the patient, if we drew lab from them,
that we want them above 5 but below 15,
otherwise we're gonna have toxicity issues.
So you can see that these aren't as
effective, they have some side effects
that patients don't enjoy and we
need to do lab monitoring for them.
That's why they're not our best choice.
However, everybody's body is different.
So there's gonna be some patients that may not
respond as well to other types of medications
and will go back to this old school one.
Every plan needs to be
individualized for the patient.
Now Theophylline is an example of a Methylxanthine
but it has some serious toxic effects
and I want you to be
aware of what those are.
But most likely, the patient's level, their
blood level will be greater than 30.
Remember that therapeutic index was
5 to 15, but once you get over 30,
you're gonna see those
Remember it used to be standardized therapy
but it's not our first choice anymore
'cause you wanna try something else.
And methylxanthines are
in the caffeine family.
Now if you are watching this, in the United
States, we usually overdose on caffeine
particulary for those of us
that are in school.
So, because you already have that stimulation
from being on a methylxanthine,
you don't wanna add a lot
of caffeine on top of it.
These meds kinda make your patient
kind of edgy when they're on them
and caffeine will also exacerbate
that and the diuretic effect.
So you wanna educate your patients and
this usually doesn't go over well.
They like to try to limit
their caffeine if possible.
But we've got some serious coffee
drinkers or even some soda drinkers
that may really become an
issue for you patient.
Unless you explain to them that
they will honestly feel better
if they limit their caffeine
while on this medications.