Skip to content

Nursing Pharmacology Ch 46 Urinary Tract Infection Drugs

  • by

All right chapter 46 ati and we’re going to be talking about utis so urinary tract infections and uh we’re going to cover four different drugs and they’re not you know we’re talking about urinary tract infections and that’s the categories that these fell in and we’ll see why for the most part but some of these drugs like the fluoroquinolones aren’t really exclusive

To urinary tract infections and this is where they fall if we go back to our classes of antibiotics and we’ve already covered let’s see we’ve already covered the cell wall in one chapter and then protein synthesis we talked about that goes all the way down here and now we’re going to talk about the sulfa drugs or the sulfonamides which metabolite production and

Then the fluoroquinolone which inhibit dna synthesis so if we look at where this falls the dna synthesis in hip inhibition is pretty straightforward you have to be able to you know unwind and and divine and that dna has to be able to divide for that cell for for the bacteria to kind of reproduce the anti-metabolites is a little more cryptic i think when we talk

About anti-metabolites it’s kind of hard to really understand it’s like what does that mean because a lot of drugs have metabolites so a can be converted into b which can be converted into c or whatever and then you have you know this active or it could be the other way where it’s breaking it down so when we talk about metabolites we’re just talking about the

Conversion of one drug two or one sorry not drug but one molecule to another it’s metabolized keep it simple for us all we’re talking about here is folic acid that’s what the sulfa drugs work on is folic acid production and you remember that folic acid or maybe you don’t remember but folic acid is also involved in dna replication now it’s not going to be the

Same as these dna synthesis inhibitors because those are more direct this is actually blocking the production of folic acid folic acid without it dna division can’t happen it’s the same with humans it’s what causes spina bifida is that that dna replication cell division can’t happen quickly enough it also can interfere with blood production blood cell production

Because blood cells have to divide to to make more blood cells and so if i tell you that this is supposed to be focused on bacterial but it can also have which which is going to predict prevent folic acid production in the bacteria but it can also somehow have an effect on on human which we can say oh well we’re going to have a hard time making blood cells then

Right maybe let’s find out actually okay we can we can leave it as a mystery but yeah okay so but we’ll we’ll try to piece that together uh and make sense out of it when we cover it so let’s talk about urinary tract infections about 75 to 95 are caused by e coli which is a type of gram negative and if we’re trying to generalize it’s really hard to generalize but

Several antibiotic medications are capable of treating utis but something like penicillin even though it is used to treat utis it’s a little it’s a little better on gram-positive they can treat gram-negative but it’s a little better on gram-positive so uh so we have kind of a favorite drug that seems to work most effectively for the e coli that cause urinary tract

Infections these kind of hit it hit it pretty hard hit it good but sulfonamide’s mixed with trimethoprim and this is a combination drug we’ll talk about the mechanisms in a minute but that’s what’s generally used fluoroquinolones so that’s a category of antibiotics are often reserved for more serious infections that may be resistant to sulfonamides they used to be

Used more often for utis but then they figured out that these worked better and fluoroquinolones can be used if if the sulfonamide trimethoprim combination doesn’t really work yeah so maybe resistant to sylvanoids and trimethoprim and then we’re going to talk about antiseptics and this term antiseptic so we have the term antiseptic and we have antibiotics so the

Question is what’s the difference well to make it easy antiseptics work on a whole lot of different things they work on bacteria yeah so they slow the growth of bacteria but they also affect fungi protozoa viruses they affect a whole lot of different organisms meanwhile antibiotics usually have some kind of specific mechanism that targets bacteria so they these

Mechanisms we’ve been talking about bacterial ribosomes things like that so so that’s the difference between an antiseptic and an antibiotic both of them can affect bacteria but antiseptics affect a whole lot of different things so let’s start with the sulfa drug sulfonamides and trimethoprim now what i want to say is we’ve got two different drugs here we’ve got

The sulfonamides and we have our sulfur methoxazole and we have trimethoprim both of these drugs prevent the synthesis of folic acid or they interfere with the synthesis or metabolism of folic acid now they both can do that individually but when what they’ve discovered is that when they’re mixed together it’s like a five to one ratio i can’t remember which one

Is more but but when they mix these together it’s more they they have more of an effect because they work on different steps remember that a to b b to c to d whatever however many steps there are one of them may be working on this step and one of them may be working on this step but when they’re used together they have the synergistic effect which means more

Than just just adding them together when they’re used together they have an increased effect so it’s like a one plus one equals three kind of an effect so trimethoprim uh sulfamec sulfamethoxazole keep on this twitch and just say sulfonamide work on different steps of bacterial folic acid synthesis so they have synergistic effect when used together so what

Are they used for urinary tract disorders associated with e coli they can also be used for ear infections so middle ear infections otitis media cancroid pertussis pneumocystis cystitis pneumonia type of pneumonia so they can also be used for other things hypersensitivity is an adverse effect which it is with with uh most antibiotics blood dyscrasia so there we

Answered our question earlier we’re saying that okay it’s preventing folic acid and it’s really focusing and targeting on bacterial folic acid production but it can have some crossover effects which is going to interfere with our own dna replication and the production of blood cells so we see these blood dysplasias leukopenia so decrease white blood cell count

Thrombocytopenia decreased thrombocyte or platelet account megaloblastic anemia so that’s red blood cells oh shoot i was going to fix this hepatotoxicity is another one it’s not supposed to be included under blood dyscrasia it’s supposed to have its own category but it’s hepatotoxic or it can be hepatotoxic which is going to be related to and i’m going to skip

Around here a little bit but kernicterus which is bilirubin formation in the brain so this is something that can happen in newborns or prenatal when the mom takes it and she’s pregnant then this it can overload the uh the liver and the liver will produce too much bilirubin when it produces so much bilirubin that it starts to kind of back up and build up in the

Brain that can be a real problem okay so uh so that’s the kernicterus so let’s go back now sorry about this to crystal urea these drugs tend to not be as water soluble so they can tend to form crystals which can obstruct the kidney they can be found in the urine you can see these crystals in the urine and a lot of times it’s just increasing water intake can

Can help can help with that that kind of solubility form uh problem in the formation of crystals and then hyperkalemia is also is also listed there let’s see um antiseptic so this term antiseptic remember that can be bacteria and it can be a whole lot of other things we’re going to focus on on its uh function of bacteria though nitropharyntoin so nitrofurantoan

Damages bacterial dna and this is interesting it um it tends to first of all nitrofuranto and tends to get immediately shuttled out of the blood and it goes through the kidneys and ends up in the urine so that’s good because that’s where our infection is so that’s that’s kind of handy and we’re going to see that happening with the uh with the antiseptic or the

Uh analgesic too so but then what happens is the bacteria take it up and uh they metabolize it and then it it’s like a it’s like a like a booby trap kind of a thing so it takes up this this near nitrofurantoan metabolizes it and then the metabolites are toxic and will kill the bacteria kind of cool so it ultimately damages bacterial dna but it’s the it’s the

Bacteria themselves that are kind of producing that toxin and yeah so it becomes 200 times more concentrated in the urine urine so at a normal dose it slows growth so it’s bacteriostatic but at high doses that are achieved in the bacteria it’s bactericidal okay so primary therapeutic use is acute utis prophylactic for recurrent utis it’s kind of handy because it

Has a different a bit of a different mechanism adverse effects gi discomfort which you’re going to see a lot hypersensitivity yes and blood dysgrazing so it may also appear with host dna replication so in this case it can also cause some of these blood dyscrac leukopenia that kind of thing uh so peripheral neuropathy paresthesia spare aesthesia is that tingling

That you have the tingling sensation in primarily the extremities the feet and the hands all right so fluoroquinolones uh ciprofloxacin o-floxacin moxifloxacin levofloxacin all the floxacin family so ciprofloxacin is the prototype it is bactericidal it inhibits the bacterial enzymes necessary to unwind dna for replication so where we were talking about folic acid

Kind of have an effect on dna this directly affects dna replication so if the dna can’t unwind then it can’t divide it can’t open up to make messenger rna it’s just stuck which is going to kill the bacteria okay so that’s why it’s bactericidal okay so it prevents it from unwinding so primary therapeutic uses it’s broad spectrum so it works on a whole lot of

Different gram-positive and gram-negative pathogens such as e coli klebsiella pneumonia alternative to parenteral antibiotics for clients who have severe infections urinary respiratory gi tract also bones joints skin soft tissues prevention of anthrax for clients who have been exposed so yes urinary is mentioned here and it does have an effect on e coli which

Is the primary pathogen for urinary tract infections but it has a whole range of other of other uses as well adverse effects the one i find interesting it’s actually a box warning is achilles tendon rupture and i can’t remember now exactly why it causes achilles tendon rupture but it does and and so yeah that’s a put a box around it it’s a box warning okay so

Photosensitivity severe sunburn sleep disturbances headache dizziness gi discomfort and of course hypersensitivity is listed there too and the last one is uh finazzo pyridine so finazopyridine is an analgesic so it reduces the pain the burning sensation so rapidly excreted unchanged in the urine so kind of like what we saw with nitrofurantoan but it’s it’s rapidly

Excreted in the urine where it has an analgesic effect on genitourinal mucosal structures we don’t know and i tried to find out exactly what it was doing to cause that analgesic effect but it’s uh it’s really i couldn’t find anything that that was certain so but yeah it’s an analgesic it reduces pain that’s what that means and it kind of accumulates in the urine

So it’s it’s pretty cool for that so primary therapeutic uses re relieves manifestations of burning with urination no that’s supposed to be urination so release manifestations of burning with urinary urination pain frequency and urgency adverse effects uh acute kidney injury and chronic injury or contraindications uh it changes the urine from an orange to a red

Color okay so it builds up in the urine pyridine is a uh is a molecule that’s kind of an orangish red color and so yeah it builds up in there and it may change the color of the urine may stain clothes so i guess that’s something you might want to say don’t don’t pee on your clothes because it may stain them yellow and may cause some gi discomfort so that’s it for this chapter

Transcribed from video
Nursing Pharmacology Ch 46 Urinary Tract Infection Drugs By Gregory Osterhaus