Hi my name is mary vuckovich and this lecture is about medication which is used for the treatment of glaucoma according to the nhmrc guidelines if you look on page 107 medication is generally the first management choice for most patients with glaucoma and medication is used to reduce intraocular pressure by enhancing aqueous outflow or by reducing aqueous production
So there are five main types of glaucoma medication and each of these have their recognized actions side effects and of course contraindications and you would have studied these in much more detail in your pharmacology subject but basically these five medication types are beta blockers prostaglandin analogues alpha-2 agonist s’ carbonic anhydrase inhibitors and
Cholinergic agents and we’re going to go through all of those in a little bit more detail in this lecture each medication family of these five has a different method of action and each one can also have significant side effects the time that it takes to achieve maximal reduction in intraocular pressure depends on both the individual patient and the type of medication
Used so it’s not just simply attributing one effect to the medication itself the initial reduction in intraocular pressure as a result of these topical medications usually occurs within minutes two hours after they go into the eye after they’re administered and maximum reduction in iop can actually take several weeks to two months even now when a patient is
Prescribed any type of topical medication for glaucoma there are several factors to consider for example the iop lowering potency of the drug the interaction with any other medications the patient might be taking or any other diseases that they might have side effects and how easily they are to administer or use and of course how affordable their the nhmrc states
That healthcare providers or ophthalmologists should choose medications based on the greatest chance of achieving target intraocular pressure the best safety profile for the drug the most convenient delivery method and being the most affordable as well now to facilitate adherence to medication health care providers should start with the simplest medication and
The most appropriate one for the patient so particularly for open-angle glaucoma treatment should be initiated at the lowest effective concentration of met and medication so you give the patient the lowest dose preferably you start them on a once daily regime at the beginning the most important thing is to help your patient adhere to treatment how do we promote
Adherence well we need to continually stress to patients that they need to persist with the medication and the management strategy because as we all know glaucoma can be site threatening if left untreated and that’s where it comes in the second point comes in where you continually need to educate your patient about the risks and prognosis of their disease it’s
Encouraged that when prescribing ophthalmologists make treatment decisions in cooperation with the patient instructions regarding the use of the medication should be written down the time of day the use number of drops a clear method of identifying the medications for example the color of the bottle this is definitely something that the orthoptera can be involved
In taking a team approach to patient management by involving all healthcare providers in glaucoma care decisions and again that’s where artists can come in communicate regularly in writing with relevant healthcare providers about glaucoma decisions so appropriate referrals and letters back to the patient’s gp for example making sure that any medications provided
To the patient have clear labels and information about their use and that’s usually something that will come from pharmacy when they pick up their medications and here’s something froth up doses it’s important that you give your patients information to help them understand their condition and glaucoma australia actually has quite a lot of resources available for
Patients about the disease and about treatment and so therefore you can actively put patients in touch with the relevant consumer groups and support groups for their particular condition let’s now take a look at the medications this this table here is from the nh and mrc guidelines of course now the pharmaceutical agents are something that you should have already
Studied in your pharmacology classes as i said before so let’s have a look first with prostaglandin analogs prostaglandin analogs are the first line agents which increase uvo scleral outflow they have about a 25 to 30 percent efficacy and the good thing about them is that they need to be used just once a day and it takes probably about 3 to 5 weeks for them to take
Their maximum prostaglandin analogs are usually well tolerated and they don’t really have a lot of systemic side effects they can cause a little bit of inflammation so even they need to be used carefully in patients that have had for example uveitis or cystoid macular edema or something like that some of the other side effects that they have is that the patient
Can develop iris pigmentation and increased eyelash growth one thing to note about trevorton is it’s now made with a slightly different preservative which is called pure light which might work better in some patients who are allergic to preservatives in eyedrops beta blockers are the next line in treatment and they’re also a first choice in treatment but there
Were previously first-line agents so it meant that they were probably more likely to be used than prostaglandin analogues and they’ve actually been in use for more than 30 years so they’ve been around for a long time what beta blockers do is they reduce aqueous production and their efficacy is about 20 to 25 percent and patients you’ll find usually use these are
The once or twice a day twice a day and there is some risk of systemic side effects they’re less effective if a patient is also on a systemic beta blocker and one of the problems is is that they can lose their therapeutic effect over time another important thing that you should remember is that beta blockers can cause depression so you should ask your patient about
Whether they’re having any side effects because your patient may not be aware that it’s the medication or that eyedrops that is causing this problem you can’t really use beta blockers in patients with asthma other respiratory diseases congestive heart disease or heart other heart problems the second choice of topical medications are alpha-2 agonist sand these have
A dual mechanism so they increase our flow of aqueous and also decrease aqueous production their efficacy is about 20 to 25 percent and they need to be used two to three times a day so quite frequently it’s possible that they have a neuro protective effect as well and it’s important to note that they take about four weeks to take effect alfe gann is the drop that’s
Shown on the right there and this is usually good for the elderly and on the left i’m showing you there i or dean this is only good for short-term use because it actually loses its efficacy so often it’s used before specific types of laser interventions just to help reduce the the iop quickly they don’t really have a lot of systemic effects but you can get things
Like dry mouth lethargy they can also aggravate depression as well as beta blockers they can interact with older style antidepressants and you can’t use these in children the next line of drugs are carbonic anhydrase inhibitors and you’ll see that they’re also second-choice or maybe even third-choice depending on which drug it is and there’s actually reduce aqueous
Production they’re a bit less powerful to their efficacy is perhaps only 15 to 20 percent and they can often take four weeks to take effect it’s important to be mindful of these some effect times because that’s when you’ll see your patients coming back for four checking of their eye intraocular pressure so they’ll be asked to come back say after four or six weeks
Depending on how long it’s suspected that the drug will work here are some carbonic anhydrase inhibitors and on the left we’ve got troost opt and a’s opt is on the right-hand side you’ll find that these medications are quite thick and soapy and they usually give the pate patients a low-grade red eye they do sting quite a bit too and leave a funny taste in the mouth
If a patient is allergic to self on amide they can’t be used and if there’s corny corneal endothelial disease they also can’t be used and they can also cause metabolic disturbances and then finally we come to cholinergic switch are right at the bottom there and these are quite effective in angle closure glaucoma and what they do is they contract the ciliary muscle
And so there are mitotic and they decrease a qui production they also increased trabecular outflow the dosage of these is four times a day which is quite a lot and it takes a week to take effect or there abouts so what i’ve got here is a bottle of i stopped a car pen for you to see but also a picture of meiosis there on the right hand side which is a side effect of
This medication patients can also get an achy brow blurred vision a myopic shift they can end up with poor pupil dilation later and also get some scarring of the conjunctiva the proprietary fixed combination drugs you’ll see on the top row there and these fixed combination drugs all contain timolol plus one other drug which i’m going to show you in the next slide
So here we have an example of what’s where so if you’ve got for example timolol plus zealot an you end up with zelich on and then timolol plus lu magan is called ganthet timolol and trevor tan is duo trev then alpha gannon tim bilal is khan began troost often timolol is co-opted and a’s opt and timolol is called as agha these fixed combination medications will most
Likely be used if the first choices are not really doing anything to change the patient’s or a little lower the patient’s intraocular pressure and here are some images of the different combination drugs or fixed combination drugs you’ve got comp again there on the bottom co soft in the middle is agha duo travel on the rides alikom and so on and you will see these
In clinic annuals you will come across these medications quite frequently so it’s very important that you are mindful of these when you’re talking to your patient about their eye drops and helping them to use them effectively and and according to the prescription it’s a good idea to mention to them that in order to help reduce the systemic absorption of the drug
Into their system they can just close their eyelids and press along they’re pumped are there in the corner of their eyes just to stop the drugs flowing down and having a greater systemic effect also something to note is that if there are two or more drops that the patient needs to use then they should leave about a five minute interval between so that they can be
Properly the first one can be properly absorbed and then the second one goes in after that so to summarize the topical medications topical medications decrease intraocular pressure and they do this in one of two ways they’ll either enhance aqueous outflow or they will reduce aqueous production and as i said there are five families of drugs so you’ve got prostaglandin
Analogues and beta blockers and these are usually the first choice of drug they in quick increase aqueous outflow and often just need to be used once a day so it’s a bit easier to start patients on these alpha-2 agonist s’ will increase aqueous outflow there a second choice in in drug as opposed to the prostaglandins and beta blockers other second choices are the
Carbonic anhydrase inhibitors and cholinergic s– both of these will decrease aqueous production as opposed to the alpha-2 agonist switch increase outflow cholinergic make a note that they’re particularly good for the product before around angle closure glaucoma and the reason that they are is because they create meiosis and then you also have the feast combination
Drops which usually are timolol and one other drug and these are often used if pace are not responding to the you know first or second choice medications and the last thing i’m going to tell you about is systemic medications so usually either a tablet or an intravenous medication that can be used for glaucoma usually these are used just in very acute situations
And they have greater systemic effects obviously because you’re either taking a tablet or you’re having the drug injected into your arm diamox reduces aqueous production and that’s usually given in tablet form so if someone comes into the clinic say with a an acute angle closure attack then they might be given diamox in addition perhaps to some some first-line
Drops to immediately reduce the intraocular pressure spike for them make them feel better it’s contraindicated in renal failure so you have to be careful i think in diabetics or anyone that potentially has got renal failure when giving that obviously orthoptera don’t prescribe it however you might be instructed by the ophthalmologist to actually administer the the
Tablet to the patient and the drops as well glycerol and mannitol are hyperosmotic agents you would have studied these in the pharmacology subject and they’re given intravenously you can’t give them to diabetics and they’re contraindicated in people who’ve got renal failure cardiac disease and hepatic disease so they’re really when it is quite a severe attack of
Walk home in the eye pressure is very very high there’s a given so that’s it in terms of medication for the treatment of glaucoma and and i’ve given you the summary there of all the all the topical medications as well so worth revising your pharmacology notes for that too
Transcribed from video
Medication for glaucoma By Meri Vukicevic
