A full drug summary about the class of drugs: Aminosalicylates
Hi guys and welcome to a full drug summary of amino salicylates let’s get started so what kinds are there the main four types are sulfasalazine mesalazine balsalazide and all salizine sodium um in terms of the structures let’s have a quick look sulfasalazine and misalign the most common sulfasalazine if broken down is broken down into mesalazine as we see on the
Left and sulfur pyridine as we’ll see on the right which will be important for the mechanism of action that we’re going to look at in just a second but just know that mesalazine on the left there is also known as five asa or five amino salicylic acid um so we know the structure of sulfasalazine mesalazine and i’m just going to tell you that all salizine has two
Mesalazines together and bowel salazide is just another pro drug of mesalazine now let’s quickly move on and it’s going to be important when i mention the difference between sulfasalazine and mesalazine with regards to ulcerative colitis versus rheumatoid arthritis so that is what the amino salicylates are used for ulcerative colitis in particular mesalazine
And rheumatoid arthritis in particular sulfasalazine and we’re going to discuss wine right now an ulcerative colitis it’s the five as rather the mesalazine which produces the therapeutic effect so we can use mesalazine so i i we’ve got a direct effect or we can use sulfasalazine which gets broken down and produces mesalazine anyway now it also produces a sulfur
Pyridine which in ulcerative colitis has no effect other than potentially causing side effects and now in terms of phosphorus of colitis this mesalazine has immunosuppressive and anti-inflammatory effects the exact mechanism of action isn’t known it’s thought to have a topical action on the colon which is why there’s so many different brands which are gastro
Resistant or prolonged release to try and ensure that they reach the colon to act on that site in particular there’s also topical preparations i.e rectal such as enemas suppositories and forms to act directly in the areas needed now in terms of rheumatoid arthritis we use sulfasalazine not mesalazine or any of the other drugs because it’s the sulfur pyridine here
That has the mechanism of action rather than the mesalazine so if we just go back a second so here we have the sulfasalazine which we would use in rheumatoid arthritis because it makes that sulfur pyridine we would use mesalazine however in ulcerative colitis because that is what we need for the anti-inflammatory and immunosuppressive effect but the sulfasalazine
Can also be used because it also produces the mesalazine and the other two all salazine and balsalicide are from my experience a lot less common but do be aware of them now there’s no evidence that one brand of mesalazine for ulcerative colitis is better than another but their release properties may differ slightly as to which areas they are most concentrated
In now in terms of side effects common side effects as with a lot of drugs gi discomfort diarrhea headaches and dizziness but the ones you should be aware of are the serious side effects such as the blood disorders um and the bone marrow suppression which would lead to lower white blood cells red blood cells and platelets and and if any blood disorders and in
Particular agranulocytosis which is dangerously low white blood cells particularly neutrophils if any of those are suspected you’d stop the drug and seek medical attention to get a blood test just to see if everything’s okay now what kind of symptoms would you expect with low white blood cells a sore throat a fever an infection with red blood cells tiredness uh
The typical symptoms of anemia with platelets increased bleeding or bruising for example now other notable side effects with sulfur salizine since we know in terms of the pre-registration exam they love asking about obscure side effects nephrotoxicity which is where we will come onto monitoring in a second as well as hyper sensitivity reactions and sulfur salizine
Specific reactions we have yellow orange coloring of body fluid in particular staining of contact lenses and also reversible um low sperm count so as soon as you stop the surface alasine your sperm count will start to come back up in terms of monitoring with amino salicylates the renal function is quite important before starting therapy at three months and then
Annually however the sulfasalazine monograph suggests that even though the manufacturer recommends it in rheumatic disease evidence of practical value is unsatisfactory now this is just for sulfasalazine in rheumatic disease but dare i say it i would recommend that renal function is just because a manufacturer recommends it i would say it’s worth testing renal
Function and with all amino salicylate in all conditions but do be aware sulfasalazine plus rheumatic disease uh renal fungi’s renal function i beg your pardon um practical value may not be uh ideal now that’s an all amino salicylates however in terms of sulfasalazine specifically it is a lot more likely to cause the bone marrow disorders the blood dyscrasius
As well as liver issues in which case we would do uh fbcs for blood count and lft’s liver function tests before therapy and then monthly for three months and that’s where the bnf cuts off um and doesn’t suggest any more tests but keep that in mind this is what the bnf suggests in other amino salicylate not sulfasalazine we would only do full blood count and liver
Function tests if adverse effects are suspected so be aware of that all amino salicylates renal function but be aware of the surface algae and exception and rheumatic disease and in terms of sulfur salisine alone full blood count and liver function tests are needed for other amino salicylates only if adverse effects are suspected now interactions with mesalazine
Ppis can increase gastric ph which makes the stomach less acidic if the ph goes up and therefore this may cause early breakdown of mesalazine which often has a ph sensitive coating to avoid the stomach to try and get as far into the intestines as possible but if you’re increasing um rather reducing the acidity of the stomach you can cause early release of that
Mesalazine which isn’t what you want because you want it concentrated in the colon for ulcerative colitis lactulose lowers the stool ph ie makes it more acidic which may prevent release of the mesalazine tablets with the ph sensitive coating in the colon because obviously they’re often resistant to acid and they keep on moving moving and moving until they reach a
More alkali area now in sulfur salisine avoid drugs which may cause myelo suppression so the blood dysplasias or hepatotoxicity hence the monitoring we’ve just covered so there’s a lot of drugs that are in that category right there be aware of them and just as an extra point aspirin is also salicylate so if a patient has an aspirin hypersensitivity this shouldn’t
Take amino salicylates thanks very much guys we’ve covered here what are the different kinds of amino salicylates in particular mesalazine and sulfasalazine and how their structures relate to each other and also the other two how their structures relate to mesalazine um we’ve talked about how mesalazine and sulfasalazine um uh biggie pardon i’ve just said that
How they’re related and what indications they are used for so the ulcerative colitis or rheumatoid arthritis for ulcerative colitis mesalazine um and all the pro drugs used regarding methylazine for rheumatoid arthritis sulfasalazine because we need to solve the pyridine in there which all the other amino acids do not produce so we’ve discussed that mechanism
Of action it’s unclear but it does have immunosuppressant effects um in terms of side effects we’ve covered common serious which is the blood dyscrasius and notable side effects we’ve covered monitoring as per the bnf um which is renal function um mainly and in sulfasalazine uh fbc’s and lfts and we’ve covered the frequencies as well and we’ve covered the main
Interactions with mesalazine sulfur salazine and we’ve covered um uh salicylate hypersensitivity and that if you’re intolerant to aspirin or rather um biggie pardon aspirin hypersensitive then you probably should not take amino salicylate either thanks for watching guys
Transcribed from video
Aminosalicylates – Full Drug Summary By Pharmacy Peninsula
