Sulfonamides
MOA of Sulfonamides
Sulfonamides inhibit bacterial folic acid synthesis by blocking the enzyme dihydropteroate synthase, which prevents bacteria from producing DNA
MOA for Penicillins
They kill bacteria by interfering with the synthesis of the bacterial cell wall, causing it to weaken and rupture
MOA for Cephlasporin
MOA of Vancomycin
It inhibits bacterial cell wall synthesis leading to cell lysis
MOA of Tetracyclines
They inhibit bacterial protein synthesis which blocks organism reproduction
MOA of aminoglycosides
They inhibit bacterial protein synthesis blocking organism reproduction
MOA of Macrolids
MOA of fluoroquinolones
They inhibit enzymes needed for DNA replication and repair
MOA for Nitrofurantoin
This medication is rapidly excreted through urine which allows it to specifically concentrate its action on bacteria causing the UTI.
Nitrofurantoin alters enzymatic activity within the bacterial cell which causes the cell to dysfunction and eventually die
Why is it important to finish the whole course for ABX TX?
Kill all the bacteria: Even if you feel better, some bacteria may still be alive. Stopping early can leave these behind.
Prevent resistance: Incomplete treatment allows surviving bacteria to develop resistance to the antibiotic, making future infections harder to treat.
Prevent relapse: Stopping early can cause the infection to come back, sometimes worse than before.
Protect others: Resistant bacteria can spread to other people, contributing to broader public health problems.
Can acyclovir cure Herpes?
No, acyclovir does not cure herpes, but it reduces the severity, duration, and frequency of outbreaks.
What is the MOA of Antifungals?
Cause direct death of invading fungus/fungal infections
A rare but serious adverse effect of this drug class includes this life-threatening skin reaction. Manifestations include burn like rashes all over and oral/throat ulcers.
Steven Johnson Syndrome
What is the most important severe adverse effect to monitor for with penicillins
Anaphylaxis
What lab values should nurses monitor when giving cephalosporins?
Kidney function (BUN, creatinine) because cephalosporins are nephrotoxic
Why is it discouraged to use Vancomycin
Vanc is usually kept as a last resort to extremely resistant bacterial infections; it is the black ops med of the ABX world
What are uses for Tetracylcines?
Acne, Lymes Disease, STIs, alt. tx to PCN
Why is Gentamycin usually administered IV or IM rather than PO
What are common gastrointestinal side effects of macrolides?
Nausea, vomiting, diarrhea, abdominal pain, and sometimes liver enzyme elevation
How should Nitrofurantoin be taken for best effect?
Food or milk
What is the difference between Aerobic and Anaerobic Bacteria
Aerobic needs Oxygen, Anaerobic does not
This sulfonamide topical agent is used to treat burns
Silver Sulfadiazine (Silvadene)
Can patients with a penicillin allergy take cephalosporins
Sometimes, you need to do a cross match for sensitivity to ensure the patient does not have a hypersensitivity to both classes of drugs
A patient receiving cefazolin prophylactically before surgery asks why the medication is being given. What should the nurse respond with?
Cephazolin provides antimicrobial coverage against susceptible organisms that could cause a surgical site infection
What types of toxicity is associated with Vanc
Why should tetracyclines not be given to children under 8 years old?
They can cause permanent yellowing or staining of developing teeth and may affect bone growth
What are nursing considerations for Gentamycin?
Assess BUN/Cr, Urine output, Tinnitus, and Dizziness
What are patient education points for Azithromycin?
Take on an empty stomach if possible, do not combine with acidic foods or drinks, use a backup method of birth control
What is an important drug interaction with fluoroquinolones?
They can bind with calcium, magnesium, iron, and zinc in antacids or supplements, which reduces absorption
How long can you use Phenazopyridine?
No more than 2-3 days!!
What is the difference between Bacteriostatic and Bactericidal
Bacteriostatic: A drug that stops bacteria from growing or multiplying. The immune system then steps up and kills the bacteria.
Bactericidal: A drug that kills bacteria directly.
Is acyclovir bactericidal or bacteriostatic?
Acyclovir is antiviral, not antibacterial, so it doesn’t fall into bacteriostatic or bactericidal categories, but it suppresses viral replication.
Patient education with Sulfonamides:
Take the medicine on an empty stomach, 1hr before and 2hrs after meals, avoid sunlight and tanning beds, increase fluid intake to 2L/day, and watch for superinfections
Report serious skin reactions (SJS) immediately
What patient education is offered to women of childbearing age who are starting PCN ABX?
If you are on oral birth control pills, make sure you use an alternative method of contraception
PCN can decrease the efficiency of Birth control pills
What is a key nursing consideration regarding IV administration of cephalosporins?
Infuse slowly to prevent phlebitis or local reactions, and monitor for signs of allergic reaction during the first dose.
Why is it important to do a med rec and full patient intake exam when giving Vanc
To see if the patient is taking other medicines that are nephrotoxic
To assess kidney function before starting abx tx
What are interactions for Tetracyclines
Dairy, Antacids, Iron
Which toxicities are associated with Aminoglycosides?
Nephrotoxicity, Neurotoxicity, and Ototoxicity
What meds can cause an interaction when taken with Azithromycin?
Anticoagulants: increased risk of bleeding
What is Antibiotic Stewardship?
Antibiotic stewardship refers to the responsible use of antibiotics to slow down resistance and ensure effectiveness for future generations
What serious side effect can occur with IV acyclovir?
Kidney damage (nephrotoxicity) or acute kidney injury if not properly hydrated during infusion
Why are Sulfonamides avoided in late pregnancy?
This med is teratogenic; increases the risk of kernicterus in newborns
A patient receiving penicillin develops wheezing, facial swelling, hypotension, and generalized urticaria shortly after the medication is administered. What is the nurse's priority action?
Administer Epi and initiate emergency treatment
What is the difference between first gen and gens 2-5 in what kinds of bacteria they target
First-generation cephalosporins are more effective against Gram-positive bacteria, while later generations (second to fifth) have increasing Gram-negative coverage
What is Red Man Syndrome and how is it prevented
Red Man Syndrome is a histamine-mediated reaction causing flushing, rash, and hypotension during infusion. It can be prevented by infusing vancomycin slowly (over at least 60 minutes).
Why should tetracyclines be avoided during pregnancy?
They can affect fetal bone and teeth development
What patient teaching is important for those receiving gentamicin?
Report any ringing in the ears, dizziness, or changes in urination; avoid other nephrotoxic medications unless prescribed; follow scheduled blood tests for monitoring.
What serious but rare side effect can occur with macrolides? (think toxicities)
Hepatotoxicity or liver injury, especially with prolonged therapy or high doses.
Patient education for Fluoroquinolones
Increase PO intake of fluids, Sun protection, avoid tanning beds, report any joint pain or tenderness, avoid dairy, calcium, antacids, and iron within 2 hrs of the dose, and watch out for s/sx of a superinfection
Obtain a culture sample before starting antibiotics to identify the bacteria causing the infection.
Perform sensitivity testing to determine which antibiotic will be most effective.
Start broad-spectrum therapy if necessary, but switch to a narrow-spectrum antibiotic once results are available.
Monitor the patient’s response and adjust treatment if needed.
When should acyclovir treatment be started for the best effect?
As soon as possible after the first signs of an outbreak, because it works best when viral replication is just beginning
A patient taking TMP-SMX develops sore throat, fever, and unusual bruising. Which laboratory test would be most important to evaluate?
What is the nurse anticipating?
Complete Blood count (CBC)
Labs that suggest Bone Marrow Suppression
A patient taking amoxicillin develops severe, watery diarrhea several days after starting therapy. Which response by the nurse is most appropriate?
Recognize possible C.Diff infection and notify the provider
A patient taking cephalexin develops facial swelling, wheezing, and hypotension shortly after a dose. Which medication should the nurse anticipate administering first and why?
A. Diphenhydramine
B. Epinephrine
C. Methylprednisolone
D. Famotidine
Epinephrine
Epi stimulates the effects of the sympathetic nervous system.
a1- vasoconstriction --> raises blood pressure and reduces airway mucosal edema
b1- increases heart rate and contractility --> supports cardiac output
b2- bronchodilation --> helps reverse bronchospasm (wheezing, SOB)
Explain Peak and Trough, when they are measured, and the importance of checking
Peak
What it is: The highest level of a drug in your blood.
When it’s measured: Usually shortly after the medication is given (like 30–60 minutes after IV infusion).
Why it matters: It shows if the dose is high enough to work against the infection.
Trough
What it is: The lowest level of a drug in your blood.
When it’s measured: Right before the next dose.
Why it matters: It ensures the drug level stays safe and not too high, preventing toxicity.
How should tetracyclines be administered to maximize absorption?
Take on an empty stomach with a full glass of water, at least 1 hour before or 2 hours after meals or supplements that contain calcium, iron, or magnesium
What are contraindications for Gentamycin?
Hearing loss or impairment, Renal Impairment or Failure, Parkinson's,
What cardiac risk is associated with Azithromycin?
Azithromycin can prolong the QT interval, increasing the risk of arrhythmias, especially in patients with heart conditions or when combined with other QT-prolonging drugs
What is a major adverse effect of fluoroquinolones on the musculoskeletal system?
Tendonitis and tendon rupture, especially the Achilles tendon; risk is higher in older adults and those on corticosteroids.
What are the therapeutic actions of ABX?
Stop cell wall growth
Prevent cell division
Prevent protein synthesis
Prevent DNA synthesis
Alter cell permeability
Which patient would be at greatest risk for an adverse effect from TMP-SMX?
A. A 24-year-old with allergic rhinitis
B. A 35-year-old with controlled asthma
C. A 72-year-old with chronic kidney disease
D. A 40-year-old with uncomplicated GERD
72 year old with CKD
Bactrim + renal impairment → ↑ toxicity risk → monitor renal function, electrolytes, CBC as appropriate
A patient taking warfarin is prescribed ampicillin. Three days later, the patient's INR has increased from 2.4 to 4.8. The patient has no active bleeding. Explain the pharmacological action.
Ampicillin can reduce vitamin K availability, potentially enhancing warfarin's anticoagulant effect.
A patient taking Warfarin is started on Fluconazole therapy. What teaching should the nurse provide the patient?
Fluconazole increases the effect of warfarin, this patient is at a higher risk for bleeds. The teaching should include methods of preventing injury and with signs to watch out for signs of bleeding