Antibiotics: Part 1 (Based off of PowerPoint only) Flashcards
Sulfonamides include
Sulfamethoxazole-trimethoprim
Others: Sulfamethoxazole Sulfisoxazole Sulfadiazine Sulfamethiozole
Mechanism of Action: Sulfonamides
- Bacteriostatic
- Inhibits folic acid synthesis
- Inhibit bacterial growth
Indications for Sulfonamides
UTI’s
Respiratory Tract
Pneumocystis jerovecii (HIV associated pneumonia)
Infections: Skin Infections & Infections dt Staph or MRSA
Contraindications for Sulfonamides
Allergy to sulfa
Adverse Effects of Sulfonamides
- Blood: agrunolocytosis, aplastic anemia, hemolytic anemia, thrombocytopenia
- GI: N/V/D, pancreatitis, hepatotoxicity
- Integumentary: Epidermal necrolysis, exfoliative dermatitis, Stevens-Johnson Syndrome, Photosensitivity
- Other: Convulsions, crystalluria, toxic nephrosis, headache, peripheral neuritis, urticaria, cough.
Interactions of Sulfonamides
• Sulfonylureas, phenytoin, and warfarin can lead to hemorrhage.
(May require frequent monitoring)
• Increases likelihood of cyclosporine-induced nephrotoxicity
• May reduce efficacy of oral contraceptives.
Nursing Process and Patient Centered Care for Sulfonamides
- Assess for drug allergies to sulfa- type drugs or sulfites (sulfonylurea), oral antidiabetic drugs and thiazide diuretics.
- Skin assessment d/t adverse effect of Stevens-Johnsons syndrome.
- Assess complete blood count before therapy d/t possibility of drug-related anemias/blood dyscrasias
- Assess renal function studies such as BUN, creatinine, urinalysis d/t potential drug-related crystalluria.
- Check pt medication and med history for manifestations of G6PD and slow acetylation
Penicillins are divided into 4 groups
- Natural PCNs
- Aminopenicillins
- Penicillinase-resistant PCNS
- Extended spectrum
Natural PCNs include
Penicillin G
Penicillin V
Aminopenicillins include
Amoxicillin
Ampicillin
Penicillinase-resistant PCNs include
Nafcillin
Dicloxacillin
Oxacillin
Cloxacillin
Extended Spectrum PCNs include
Amoxicillin/clavulanic acid
Ampicillin/sulbactam
Ticarcillin/clavulanic acid
Piperacillin/tazobactam
Mechanism of Action: PCNs
Bactericidal
Inhibits cell wall synthesis. How?
Adverse Effects of PCNs
Related to drug allergies/Type 1 hypersensitivity reaction
• Most common reactions are urticaria, pruritus and angioedema.
• Unpredictable reactions: maculopapular eruptions, eosinophilia, Stevens-Johnson syndrome and exfoliative dermatitis.
- CNS: Lethargy, anxiety, depression, seizures.
- Hematologic: N/V/D taste alterations, oral candidiasis.
- Metabolic: hyperkalemia, hypernatremia, alkalosis
- Skin: Pruritus, hives and rash
Indications for PCNs
Infections - depends on pathogen and PCN class: Gram + Strep, Enterococcus, Staph infections;
Gram - and anaerobes moderate to severe infections
(i.e. Piperacillin/tazobactam);
PCN for prophylaxis (i.e. Amoxicillin)
Contraindications for PCNs
Allergy (very common, incidence ~ 0.7% to 4%)
Drug Interactions of PCNs
- Aminoglycosides (IV) and clavulanic acid -> more effective killing of bacteria
- Methotrexate -> decreases renal elimination of methotrexate -> increases methrotrexate levels
- NSAIDs: compete for protein binding -> more free and active penicillin
- Oral Contraceptives: uncertain -> may decrease efficacy of contraceptive
- Probenecid: competes for elimination -> prolongs the effects of penicillins
- Rifampin: inhibition -> may inhibit the killing activity of penicillins
- Warfarin: reduced vitamin K from gut flora -> enhanced anticoagulant effect of warfarin.
Nursing Process & Patient Centered Care: Patient Teaching (pp. 617-620) for PCNs
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Cephalosporins
First - Fifth Generations (Table 38-6, p. 610)
First Generation Cephalosporins
Cefazolin
Has the most gram + coverage.
Treats infections caused by gram + bacteria, penicillinase-producing organism and some gram-negative organisms.
Used for preoperative and postoperative prophylaxis.
Second Generation Cephalosporins
Cefoxitin and Cefuroxime
Treat infections. Less coverage of gram-positive organisms and greater coverage of gram-negative and anaerobic organisms.
Only generation with anaerobic coverage
Third Generation Cephalosporins
Ceftriaxone and Ceftazidime
Ceftazidime: Infections; more extensive coverage of gram-negative organisms, including Psuedomonas spp.
Ceftriaxone: comparable to those for ceftazidime, except for psuedomonas spp.
Fourth Generation Cephalosporins
Cefepime
Infections
Provides more extensive coverage of gram-negative organisms and better gram-positive coverage than third-generation, including organisms causing intraabdominal infections.
Fifth Generation Cephalosporins
Ceftaroline
Is broad spectrum (including MRSA) and covers gram - and gram + organisms (except for psuedomonas and acinetobacter).
Has the most gram - coverage.
Mechanism of Action: Cephalosporins
- Bactericidal
- Disrupt bacterial cell wall -> lysis and death
- Depends on generation, level of gram negative coverage increases as generation increases
Indications for Cephalosporins
moderate to severe infections and choice of drug depends on pathogens and generation
Contraindications for Cephalosporins
Allergy to cephalosporins and PCNs
Renal disease
Adverse Effects of Cephalosporins
Similar to PCNs.
Most commonly reported are mild diarrhea, abdominal cramps, rash, pruritus, redness and edema.
Interactions of Cephalosporins
- Ethanol (alcohol): Accumulation of acetaldehyde metabolite of ethanol -> acute alcohol intolerance after drinking alcoholic beverages with 72 hrs of taking cefotetan. Symptoms include stomach cramps, N/V, diaphoresis, pruritus, headache and hypotension.
- Antacids, iron: decreases absorption of certain oral cephalorsporins -> decreased effectiveness of the drug.
- Probenecid: decreased renal excretion -> increased cephalosporin levels
- Oral Contraceptives: unknown -> increased risk for unintended pregnancy.
Nursing Process & Patient Centered Care: Patient Teaching (pp. 617-620)
for Cephalosporins
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Carbapenems include
Imipenem/cilastatin
Adverse Effects of Carbapenems
CNS (most serious: seizure esp. in elderly)
Nursing Process & Patient Centered Care: Patient Teaching (pp. 617-620) for Carbapenems
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Mechanism of Action: Carbapenems
Binds to penicillin binding proteins inside bacteria, inhibits bacterial cell wall synthesis
Indications for Carbapenems
Severe infections of the skin and soft tissues, bones, joints, endocarditis, intraabdominal, respiratory
UTIs
Septicemia
Contraindications for Carbapenems
Allergy to carbapenems and local anesthetics such as lidocaine
Renal Disease
Monobactam includes
aztreonam
Mechanism of Action: Monobactam
Inhibits bacterial cell wall synthesis causing lysis
Indications for Monobactam
moderate to severe infections
Contraindications for Monobactam
Allergy
Adverse Effects for Aztreonam
Skin and GI effects (more common)
Interactions for Aztreonam
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Nursing Process & Patient Centered Care: Patient Teaching (pp. 617-620) for Aztreonam
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Macrolides include
azithromycin (Zithromax, Z-Pak)
clarithromycin (Biaxin)
dirithromycin (Dynabac)
erythromycin (E-Mycin, Erythrocin)
Mechanism of Action: Macrolides
- Bacteriostatic
- Bactericidal in high dosage
- Binds to 50s bacterial ribosomes, inhibit protein synthesis, suppress bacterial growth
Indications for Macrolides
- Infections of the skin and soft tissues, respiratory tract, sexually transmitted disease
- Alternative drug for patients allergic to PCNs
- For prophylaxis
Contraindications for Macrolides
Allergies
Adverse Effects of Macrolides
Refer to Table 38-8, p. 614
Interactions of Microlides
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Nursing Process & Patient Centered Care: Patient Teaching (pp. 617-620) for Macrolides
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Tetracyclines include
demeclocycline (Declomycin) doxycycline (Vibramycin, others) minocycline (Minocin, others) tetracycline (sumycin, others) tigecycline (Tygacil)
Mechanism of Action: Tetracyclines
Bacteriostatic
Binds to 30s bacterial ribosomes, inhibit protein synthesis, suppress bacterial growth
Indications for Tetracyclines
Infections of the skin and soft tissues (acne, gum disease), sexually transmitted disease; respiratory tract, intraabdominal
Contraindications for Tetracyclines
Allergy and pregnancy
Adverse Effects of Tetracyclines
GI
Bones & teeth
Superinfection (e.g. vaginal candidiasis)
Hepatotoxicity
Photosensitivity
Vestibular toxicity (dizziness, unsteadiness)
Interactions of Tetracyclines
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Nursing Process & Patient Centered Care: Patient Teaching (pp. 617-620) for Tetracyclines
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Patient Teaching for Sulfonamides
- Encourage increased in fluids, preferably water to prevent drug-related crystalluria)
- Encourage patients to immediately report the following to the HCP: worsening ab cramps, stomach pain, diarrhea, blood in the urine, severe or worsening rash, SOB, and fever – May indicate adverse reactions to these drugs.
