Pharm, part 48: Immune Medications - Antibiotics - Others

by Cathy Parkes September 25, 2021 Updated: April 14, 2022 6 min read

In this article, we continue our coverage of antibiotics. In the two previous articles, we focused on antibiotics that affect protein synthesis and cell wall synthesis. Here, we discuss antibiotics that affect the bacterial cell in other ways.

The Nursing Pharmacology video series follows along with our Pharmacology Second Edition Flashcards, which are intended to help RN and PN nursing students study for nursing school exams, including the ATI, HESI, and NCLEX.

Cool Chicken When you see this Cool Chicken, that indicates one of Cathy's silly mnemonics to help you remember. The Cool Chicken hints in these articles are just a taste of what's available across our Level Up RN Flashcards for nursing students!

Fluoroquinolones: ciprofloxacin (Cipro), levofloxacin

Fluoroquinolones, including ciprofloxacin and levofloxacin are antibiotics used to treat a number of bacterial infections, including urinary tract infections (UTIs), bone and joint infections, respiratory infections, and anthrax.

Mode of action of ciprofloxacin and levofloxacin

The mode of action of this medication class is to inhibit DNA synthesis in the bacteria.

Side effects of ciprofloxacin and levofloxacin

Side effects include diarrhea, superinfection (e.g., C. diff) that causes severe diarrhea and colitis (an inflammatory reaction in the colon), photosensitivity, and an increase in liver enzymes. This medication also carries a black box warning due to the risk for tendon rupture — unique to this medication class.

Sulfonamide: trimethoprim/sulfamethoxazole (Bactrim)

Trimethoprim sulfamethoxazole is an antibiotic that is used to treat a number of bacterial infections, including UTIs, respiratory infections, and middle ear infections.

Mode of action of trimethoprim sulfamethoxazole

The mode of action of this medication class is to inhibit folic acid synthesis in the bacteria.

Side effects of trimethoprim sulfamethoxazole

Side effects include GI upset, blood dyscrasias (a disorder of the blood, which can cause anemia), thrombocytopenia, and leukopenia. Other side effects include photosensitivity, crystalluria (cloudiness in the urine caused by crystals in the urine), as well as Stevens-Johnson syndrome, which is a very severe rash.

Nursing care for patients receiving trimethoprim sulfamethoxazole

In terms of nursing care, assess the patient for sulfa allergies prior to administration of this medication (note that the word “sulfa” is part of the drug name, an easy way to remind you to make this assessment).

Monitor the patient’s CBC levels due to the risk of blood dyscrasias.

Encourage the patient to increase their fluid intake in order to prevent the side effect of crystalluria.

Urinary tract antiseptic: nitrofurantoin (Macrobid)

Nitrofurantoin is an antibiotic that is used to treat UTIs.

Mode of action of nitrofurantoin

The mode of action of nitrofurantoin is to inhibit bacterial enzymes that are required for DNA, RNA, and cell wall synthesis.

Side effects of nitrofurantoin

Side effects include GI upset, hypersensitivity, pulmonary toxicity (damage to the lungs), peripheral neuropathy (damage to the peripheral nerves (those located outside of the brain and spinal cord), and brown discoloration of the urine.

Nursing care for patients receiving nitrofurantoin

In terms of nursing care, alert the patient about the discoloration of their urine. Also, advise them to take this medication with food.

Antiprotozoal: metronidazole (Flagyl)

Metronidazole is another common antibiotic administered in the hospital setting. It can be used for bacterial infections and protozoan infections.

Mode of action of metronidazole

The mode of action of metronidazole is to inhibit DNA and protein synthesis. It is also effective against anaerobic bacteria. Anaerobic bacteria are part of the normal flora of human skin and mucosal membranes and do not require molecular oxygen to grow.

Side effects of metronidazole

Side effects include GI upset, metallic taste, dark urine, dizziness, and headache.

This medication carries a black box warning due to the risk for cancer.

Patient teaching when administering metronidazole

In terms of patient teaching, advise the patient not to drink alcohol when they are taking metronidazole.


Full Transcript

Hi, I am Cathy, with Level Up RN. In this video, I'm going to continue my coverage of antibiotics. In our last two videos, we talked about antibiotics that affect protein synthesis and cell wall synthesis. In this video, we are going to talk about antibiotics that affect the bacterial cell in other ways. At the end of the video, I'm going to provide you guys a little quiz to test your knowledge of some of the key points I'll be covering in this video. So definitely stay tuned for that. And if you have our pharmacology flashcard, definitely pull those out so you can follow along because we won't go through every single detail that's on these cards, but I'll try to hit the highlights.

First up, we have our fluoroquinolones, which include ciprofloxacin and levofloxacin.

These antibiotics are used to treat a number of bacterial infections, including UTIs, bone and joint infections, respiratory infections, as well as anthrax.

They work by inhibiting DNA synthesis in the bacteria.

Side effects include diarrhea, superinfection such as C. diff, photosensitivity, and increase in liver enzymes, and this medication also carries a black box warning due to the risk for tendon rupture, which is definitely unique to this medication class.

Our little cool chicken hint for helping you to remember this drug class and one of the key side effects of this drug class is if you look at the words ciprofloxacin and levofloxacin, they both have that flox, which reminds me of fox. So if you remember that that fox likes to eat tendons, then I'll help you remember that these medications can result in tendon rupture.

Next up, we have trimethoprim sulfamethoxazole, which is an antibiotic that is used to treat a number of bacterial infections such as UTIs, respiratory infections, and middle ear infections.

The mode of action of this medication class is that it inhibits folic acid synthesis in the bacteria.

Side effects include GI upset, blood dyscrasias, which can cause anemia, thrombocytopenia, and leukopenia. Other side effects include photosensitivity, crystalluria, as well as Stevens-Johnson syndrome, which is a very severe rash.

In terms of nursing care, we're going to want to assess the patient for sulfa allergies prior to administration of this medication, and if you look at the drug name, it includes sulfa in there, so that will help you remember that you need to do that. Other nursing care items include monitoring the patient's CBC levels because of the risk of blood dyscrasias.

We also want to encourage the patient to increase their fluid intake in order to prevent that crystalluria side effect.

Next up, we have nitrofurantoin, which is an antibiotic that is used to treat UTIs.

It works by inhibiting bacterial enzymes that are needed for DNA, RNA, and cell wall synthesis.

Side effects include GI upset, pulmonary toxicity, peripheral neuropathy, and brown discoloration of the urine. So you definitely want to give your patient a heads up about that discoloration so they're not alarmed and also advised them to take this medication with food.

All right. Next, we have metronidazole, which is another common antibiotic that we administer in the hospital setting. Metronidazole can be used for bacterial infections, as well as protozoan infections.

So it inhibits DNA and protein synthesis, and it is also effective against anaerobic bacteria.

Side effects include GI upset, metallic taste, dark urine, dizziness, and headache.

In terms of patient teaching, you want to advise your patient to not drink alcohol when they are taking metronidazole.

Our little cool chicken hint here on the card to help you remember at least one of the side effects of metronidazole, if you look at the word metronidazole, it starts with M-E-T, and metallic taste also starts with M-E-T. So hopefully that's helpful.

All right, time for quiz. I have three questions for you. First question, patients taking trimethoprim sulfamethoxazole should be advised to increase their fluid intake due to the risk of blank. The answer is crystalluria. Question number two, what antibiotic carries a black box warning due to the risk of tendon rupture? The answer is ciprofloxacin or levofloxacin. Question number three, metallic taste is an expected side effect with metronidazole. True or false? The answer is true.

Okay. I hope this video has been helpful. Can I get a thumbs up for saying all these drug names? [laughter] It took a few takes to get them right. So take care and good luck with studying.


Leave a comment

Comments will be approved before showing up.


Related Posts

Pharm, part 43: Reproductive Medications - Testosterone, BPH and Erectile Dysfunction

Pharm, part 43: Reproductive Medications - Testosterone, BPH and Erectile Dysfunction

by Cathy Parkes Sep 21, 2021 7 min read

The following drug classes and medications: androgens (testosterone), androgen inhibitors (finasteride), peripherally acting antiadrenergics (tamsulosin, doxazosin), and phospodiesterase 5 inhibitors (sildenafil, tadalafil).
Read Article
Pharm, part 42: Reproductive Medications - Estrogen, Progesterone, Uterine Stimulants, Tocolytic Agents

Pharmacology, part 42: Reproductive Medications - Estrogen, Progesterone, Uterine Stimulants, Tocolytic Agents

by Cathy Parkes Sep 20, 2021 8 min read

Estrogens (conjugated estrogen, estradiol), progesterones (medroxyprogesterone, norethindrone), uterine stimulants (oxytocin, methylergonivine), tocolytic agents (terbutaline).
Read Article
Pharm, part 41: Renal Medications - Diuretics

Pharmacology, part 41: Renal Medications - Diuretics

by Cathy Parkes Sep 15, 2021 9 min read

Learn about these diuretics: loop diuretic (furosemide), thiazide diuretic (hydrochlorothiazide), potassium sparing diuretic (spironolactone), and osmotic diuretic (mannitol).
Read Article