Ch 38 Antibiotics Part 1 Flashcards
When can a superinfection occur?
It can occur when antibiotics reduce or completely eliminate the normal bacterial flora.
- Serious superinfection can cause antibiotic-associated colitis ->
overgrowth of C dif
What is empiric therapy?
The antibiotic selected is one that can best kill the microorganisms known to be the most common causes of the infection.
What are some characteristics of the antibiotic Sulfonamides?
- bacteriostatic antibiotic
- broad spectrum of antibacterial activity
- effective against both Gram + and Gram -
What is the main indication for Sulfonamides administration?
- Treatment of UTIs because of its high concentration in the kidneys
What are 4 other indications for the use of Sulfonamides combination SMX-TMP? (Sulfamethoxazole/trimethoprim)
- Respiratory tract infections
- Prophylaxis
- Tx of opportunistic infections in pts w/ HIV
- Tx of staphylococcus infections
What are the most common adverse effects of Sulfonamides?
- fever
- rash
- photosensitivity reactions
- reduced blood count levels (thrombocytopenia, hemolytic anemia, aplastic anemia)
- Stevens-Johnson syndrome
- nausea, vomiting, diarrhea
- hepatotoxicity, nephrotoxicity
What does the nurse need to consider if the patient is allergic to Sulfonylureas (antidiabetic) and Thiazide diuretics?
The patient is also probably allergic to Sulfonamides.
What interactions can be caused w/ Sulfonamides?
- Antibiotics
- potential hypoglycemic effects w/ diabetic pts
- decrease effects of oral contraceptives
- hemorrhage when using w/ Warfarin
Why should the nurse encourage the patient to ⬆ fluids to 2000 to 3000 mL/24 h when on Sulfonamides?
To prevent drug-related crystalluria.
When is an antibiotic therapy said to be subtherapeutic?
When the S x S do NOT improve.
What are the 4 subclasses of Beta-lactams?
1) Penicillins
2) Cephalosporins
3) Carbapenems
4) Monobactams
What are the 3 main characteristics of Penicillins?
- Beta-Lactam Antibiotics
1) Bactericidal antibiotic
2) Natural Penicillins:
- effective on Gram + bacteria (strep, entero, staph)
3) Extended-spectrum Penicillins
- effective on Gram - bacteria (used commonly for HAIs)
What are some of the common adverse effects of the Penicillin and Cephalosporin drugs?
1) CNS - Coma, hallucinations, anxiety, twitching, lethargy, seizures.
2) GI - Nausea, vomiting, diarrhea, abdominal pain, colitis, taste alterations, oral candidiasis, and ⬆ ALT and AST levels.
3) Hematologic - Anemia, ⬆ bleeding time, bone marrow depression, granulocytopenia.
4) Metabolic - Hyperkalemia, hypokalemia, alkalosis
5) Skin - Rash, hives, pruritus
What beverages should be avoided when taking penicillins (Beta-lactams)?
- caffeine
- citrus fruit and cola
- fruit juices
- tomato juice
What are the 2 main characteristics of Cephalosporins (Beta-lactams)?
1) Bactericidal antibiotic
2) Active against:
- Gram +
- Gram -
- Anaerobic bacteria
- Not effective against fungi and viruses
What are the known interactions w/ Cephalosporins?
- Alcohol
- Antacids
- Oral contraceptives
What are the 6 S x S the patient should immediately report when taking Cephalosporins (Beta-lactams)?
1) Diarrhea
2) Foul-smelling, loose or bloody stools
3) Flu-like symptoms
4) Blistering of skin
5) Dyspnea
6) Seizures
What are the 5 main characteristics of Carbapenems (Beta-lactams)?
1) Bactericidal antibiotic
2) Broadest antibacterial action of all antibiotics
3) Effective against many gram +
4) Small risk of cross allergenicity w/ pts allergic to penicillin
5) MUST be infused over 60 min
What is the main undesirable effect of Carbapenems (Beta-lactams)?
Drug-induced seizures
What are the 3 main characteristics of Monobactams (Aztreonam)?
1) Bactericidal antibiotic
2) Aztreonam is the only antibiotic of its category
3) Primarly active against aerobic gram - such as E. coli, Klebsiella spp and Pseudomonas spp
What are Monobactams (Beta-lactams) indicated for?
- Moderately severe systemic infections
- UTIs
What are some possible adverse effects of Monobactams (Aztreonam)?
- Rash
- Nausea
- Vomiting
- Diarrhea
What is the main characteristic of Macrolides? (Erythromycin, Azithromycin, Clarithromycin)
- are considered bacteriostatic = inhibit growth but do not kill
What are some indications for the use of Macrolides?
- Upper and lower respiratory tract infections
- Syphilis
- Lyme disease
- Gonorrhea
- irritates the GI tract which stimulates smooth muscle and GI motility
- facilitates the passage of feeding tubes from the stomach to the small bowel
- HAIs
- active ulcer
