Antibiotics Flashcards
Beta-lactam antibiotics (properties, type of Abx, MOA)
- They have a beta-lactam ring
- It’s bactericidal antibiotics. They kill bacteria, both gram +ve and gram -ve, since all gram + and - bacteria have peptidoglycan in their cell walls
- MOA: inhibit cell wall synthesis. They do this by binding on transpeptidase enzymes, which is needed to create linkage between the peptides and hold the cell wall together, inhibiting its action
Beta-lactam Abxs resistance
- Altering porins in the cell walls that may change the right size and/or charge, not allowing the Abx to get into the cell (Gram -ve)
- Beta-lactamase enzyme can change the chemical structure of the Abx by cleaving a C-N bond (Gram -ve and +ve)
- Change in structure of the transpeptidase, not allowing Abx to bind to the enzyme (MRSA resistant to all penicillin)
- Efflux pump that constantly pumps the Abx out of the cell and they cannot bind to transpeptidase
Cefuroxime (Indications, MOA, Therapeutic effects, Spectrum, Contraindication, Cautious usage, Adverse reactions/side effects)
Indications: treatment of respiratory tract infections, skin infections, bone and joint infections, urinary tract infections
MOA: binds to bacterial cell wall membrane, causing cell death
Therapeutic Effects: bactericidal
Spectrum: active against gram-positive and gram-negative aerobic bacteria
Contraindicated in: hypersensitivity to cephalosporins; serious hypersensitivity to penicillins
Use cautiously in: renal impairment (will need dose adjustments)
Adverse reactions/side effects: rash and Costridioides Difficile-Associated Diarrhea (CDAD)
Cefuroxime Pharmacokinetics (absorption, distribution, and metabolism and excretion)
- Absorption: Well absorbed following IV, IM and PO administration
- Distribution: Widely distributed. Well penetrated into CSF if IV used
- Metabolism and excretion: Excreted primarily unchanged by the kidneys
Cefuroxime Nursing Implications
- Assess patient for infection (vital signs, appearance of wound if they have any, sputum, urine, and stool, WBC) at beginning of and throughout therapy
- Before initiating therapy, obtain a history to determine previous use of and reactions to penicillins or cephalosporins
- Obtain specimens for culture and sensitivity before initiating therapy. First dose may be given before giving results
- Observe for S+S of anaphylaxis (rash, pruritus, laryngeal edema, wheezing)
- Monitor bowel function. Diarrhea, abdominal cramping, fever, and bloody stools
Cefpodoxime (Indications, MOA, Therapeutic effects, Spectrum, Contraindication, Cautious usage, Adverse reactions/side effects)
Indications: treatment of respiratory tract infections, skin infections, bone and joint infections, urinary tract infections
Mechanism of Action: bind to bacterial cell wall membrane, causing cell death
Therapeutic Effects: bactericidal
Spectrum: active against gram-positive and gram-negative aerobic bacteria
Contraindicated in: hypersensitivity to cephalosprins; serious hypersensitivity to penicillins
Use cautiously in: renal impairment (will need dose adjustments)
Adverse reactions/side effects: rash, Clostridioides Difficile-Associated Diarrhea (CDAD)
Cefpodoxime Pharmacokinetics (absorption, distribution, and metabolism and excretion)
-Absorption: 50% absorption in the GI tract after being converted from protype to active form
-Distribution: Widely distributed. Well penetration into CSF better than Cefuroxime
-Metabolism and excretion: 30% excreted in urine
Cefpodoxime Nursing Implications
- Assess patient for infection (vital signs, appearance of wound if they have any, sputum, urine, and stool, WBC) at beginning of and throughout therapy
- Before initiating therapy, obtain a history to determine previous use of and reactions to penicillins or cephalosporiins
- Obtain specimens for culture and sensitivity before initiating therapy. First dose may be given before giving results
- Observe for S+S of anaphylaxis (rash, pruritus, laryngeal edema, wheezing)
- Monitor bowel function. Diarrhea, abdominal cramping, fever, and bloody stools
Amoxicillin-Clavulanate (Indications, MOA, Therapeutic effects, Spectrum, Contraindication, Cautious usage, Adverse reactions/side effects)
Indications: treatment of respiratory tract infections, skin infections, otitis media, bone and joint infections, and urinary tract infections.
Mechanism of Action:
-Amoxicillin: bind to bacterial cell wall membrane, causing cell death
-Clavulanate: inhibits the action of beta-lactamase – an enzyme produced by bacteria that is capable of inactivating amoxicillin
Therapeutic Effects: bactericidal
Spectrum: active against gram-positive and gram-negative aerobic bacteria
Contraindicated in: hypersensitivity to penicillins or clavulanate
Use cautiously in: renal impairment (will need dose adjustments)
Adverse reactions/side effects: rash, Clostridioides Difficile-Associated Diarrhea (CDAD)
Amoxicillin-Clavulanate Pharmacokinetics (absorption, distribution, and metabolism and excretion)
- Absorption: Well absorbed in the GI tract
- Distribution: Widely distributed. Does not readily enter the brain/CSF
- Metabolism and excretion: 70% excreted unchanged in the urine; 30% metabolized in liver
Amoxicillin-Clavulanate Nursing Implications
- Assess patient for infection (vital signs, appearance of wound if they have any, sputum, urine, and stool, WBC) at beginning of and throughout therapy
- Before initiating therapy, obtain a history to determine previous use of and reactions to penicillins or cephalosporins
- Obtain specimens for culture and sensitivity before initiating therapy. First dose may be given before giving results
- Observe for S+S of anaphylaxis (rash, pruritus, laryngeal edema, wheezing)
- Monitor bowel function. Diarrhea, abdominal cramping, fever, and bloody stools
General MOA of anti-ribosomal Abx
All cells need protein production to survive and ribosomes play a significant role in protein production through mRNA. Anti-ribosomal Abx inhibit ribosomal action, which inhibit growth and survival
NOTE: bacterial ribosomes are different form human ribosomes. It will not inhibit the function of our ribosomes
Azithromycin (Indications, MOA, Therapeutic effects, Spectrum, Contraindication, Cautious usage, Adverse reactions/side effects)
Indications:
- Upper respiratory tract infections (e.g., bacterial exacerbations of chronic bronchitis)
- Lower respiratory tract infections (e.g., bronchitis or pneumonia)
Mechanism of Action:
-Inhibits protein synthesis at the level of the 50S bacterial ribosome
Therapeutic Effects: bacteriostatic action
Spectrum: active against gram-positive and gram-negative aerobic bacteria
Contraindicated in:
- Hypersensitivity to azithromycin or other macrolide anti-infectives
- History of hepatic dysfunction with prior use of azithromycin
Use cautiously in:
- Severe hepatic impairment (may need dose adjustment)
- Severe renal impairment (CCr < 10 mL/min)
Adverse reactions/side effects:
- Torsades de points (abnormal heart rhythm that can lead to sudden cardiac arrest)
- Acute generalized exanthematous pustulosis (skin reaction – skin eruptions)
- Drug reaction with eosinophilia and systemic symptoms (DRESS) (Rash with fever, general malaise, eosinophilia [excess eosinophil formation], lymphocytosis [increase in white blood cells], multi-end organ dysfunction)
- Abdominal pain, diarrhea, nausea
Azithromycin Pharmacokinetics (absorption, distribution, and metabolism and excretion)
- Absorption: Rapidly absorbed (40%) after oral administration
- Distribution: Widely distributed to body tissues and fluids
- Metabolism and excretion: Mostly excreted unchanged in bile
Azithromycin Nursing Implications
- Assess patient for infection (vital signs, appearance of wound if they have any, sputum, urine, and stool, WBC) at beginning of and throughout therapy
- Obtain specimens for culture and sensitivity before initiating therapy. First dose may be given before giving results
- Observe for S+S of anaphylaxis (rash, pruritus, laryngeal edema, wheezing)
- Assess patient for skin rash frequently during therapy. Discontinue at first sign of rash
- May cause increases in serum bilirubin, AST, ALT, LDH, and alkaline phosphatase – liver enzymes that indicate liver dysfunction
