antimalarial drugs such as chloroquine and hydroxychloroquine also known more
famously as Plaquenil are not only being used to treat malaria but are currently
being tested to help treat new viral infections but they are more famously
used help with symptoms of autoimmune diseases such as rheumatoid arthritis
lupus and even Sjogren's syndrome but these medications are considered
high-risk and potentially toxic to the body particularly within the retina and
the back of the eye and can even lean to retinal cell death and permanent vision
loss so in this video we're going to review how Plaquenil affects the eye and
what type of special testing you can expect to see if you were ever put on
these medications let's take a look
hello and welcome this is Dr. Allen here from the doctor Eye Health show helping you
learn all about the eyes and vision now high-risk medications such as
chloroquine and hydroxychloroquine have a long running history of known systemic
complications however they also do help a lot of people chloroquine originally
was developed as an antimalarial drug to fight malaria a serious but
thankfully very rare infection caused by mosquito bites
later on hydroxychloroquine also known by its brand name Plaquenil
was developed as a derivative of chloroquine and he's generally used more
often due to its better safety profile than its predecessor chloroquine and
outside of just malaria treatment these medications are known to help people
with chronic autoimmune conditions such as rheumatoid arthritis and lupus and
eye doctors like myself often see patients on these medications for these
conditions the issue is that these medications are known to cause retinal
toxicity and if not caught early enough can lead to permanent retinal cell death
and vision loss now it's not fully understood how Plaquenil affects the
retina in the back of the eye it's believed to somehow inhibit retinal cell
metabolism as well as bind onto melanin cells within the retinal pigment
epithelium that's the far back layer of the retina right behind the
photoreceptor cells most eye doctors know plaquenil toxicity by what's called
bull's eye retinopathy that's where the retina in the back of the eye takes the
appearance of a dark bull's eye right in the macula unfortunately the retina
only appears like this bullseye in a very severe end stages of retinal
toxicity from these medications that is exactly why early detection of plaquenil
toxicity is so important now that we have reviewed what plaque removal is
used for and how to fix the eye let's go over the different tests that you'll see
in the eye clinic if you've ever put on these medications but first let me know
in the comments section if you've ever used any of these medications and what
your personal opinion is about them now keep in mind that recommendations do
change with updated research but at the current timing of this video these are
the screening tools that typically you will expect to see if you go see your
eye doctor from being put on these medications usually before starting
these medications or right about the time when you're first taking your
initial dose your rheumatologist or your prescribing physician will recommend you
see either an optometrist or an ophthalmologist to have these screening
tests done the first thing is that you're gonna be asked to have a full eye
exam with dilation so that their pupils will be dilated with the eyedrops that
nobody likes so that we can see inside the back of the eye and make sure that
the retina is in good shape this may include or may not include retinal
photographs as a baseline along with just a dilated retinal exam you can
expect to have a 10-2 central visual field test this is a test where you will
look inside of a big instrument with a dot in the middle and while staring at
that dot they flash these white lights and you simply click a button if you
think you see the flashing lights these lights have gradually changed in both
brightness and locations so that your doctor can map out how your side vision
is really functioning subtle changes to the retinal health can be picked up with
this test and it can be a little challenging so don't be surprised if
your eye doctor does recommend running this test again in the future if you
have a tough time with it after these two standard tests then your eye doctor
will order at least one of the following tests could be one getting a retinal
photograph using fundus autofluorescence which really highlights and measures
where in the retina that active metabolism is changing it could be from
electroretinogram or a multifocal ERG this is an instrument where it
actually measures the electro responses of the retina and is extremely
sensitive for picking up changes with retinal health and then they could be
using a standard domain optical coherence tomography which is also known
as an SD OCT which is basically like getting an ultrasound of the retina in
the back of the eye gives us very high definition images of the retinal cells
and can even show us when retinal cells are dying even before having visual
changes I think that if you are going to be screened or tested for plaque no
toxicity you're more likely going to see that OCT imaging just because it's more
widely available than these other tests however if your doctor does have access
to a multifocal ERG they're probably going to order that because it is so
sensitive for this sort of disease now again all of these testing are usually
done right before starting plaque well or right about the same time as starting
plaque Whannell however these tests are usually only recommended to be done
again after using the medication consistently for about five years
however with that being said from my personal experience talking to other eye
care professionals around the country and the world as well as speaking with
rheumatologists who prescribe Plaquenil the most frequently they usually
recommend still testing with this sort of Plaquenil screening pretty much every
single year just because the risk of retinal toxicity and the permanent
damages that can occur is so serious one of the reasons why Plaquenil toxicity to
the retina is so serious is that even if your eye doctor catches it and have you
taken off of the medication that damage to the retina can still continue
that's because Plaquenil is known to again bind those photoreceptor pigment
cells in the back of the eye and it may continually do damage over time plaque
will no clues from the body very slowly from both the kidneys and the liver and
can be found even years later after stopping its use now thankfully the
overall risk for developing plaquenil toxicity is very low it's only about 1%
after taking that medication for five years however there are some other
associations with higher risk for retinal toxicity the greater risk
factors are being over the age of 60 having a previously diagnosed retinal
disease such as macular degeneration having other known renal or
liver disease because again the medication is cleared through those
routes as well as being on the medication greater than five years as
taking high dosages of the medication or really your overall cumulative dose
these are all things that your eye doctor will consider when recommending
when the next time you should be screened for retinal toxicity due to
plaque Whannell so if you ever put on a medication such as chloroquine or
hydroxychloroquine for things like anti malarial reasons or for an autoimmune
condition make sure to talk with your rheumatologist your prescribing
physician or your eye doctor about the possible effects on the eye health and
the appropriate testing otherwise I hope you got value out of this video if you
did smash that like button for me and drop a comment in the section below
otherwise keep an eye on it and we'll talk to you soon