Upgrade to remove ads
Only $35.99/year

chapter 26 - Antibacterials

Terms in this set (46)

Antibiotics- bacteriostatic drugs
inhibit growth of bacteria, tetracycline and sulfonamides
antibiotics- bactericidal drugs
kills bacteria, penicillins and cephalosporins
antibacterials mechanism of action
inhibition of bacterial cell wall
alteration of mechanism permeability
inhibition of protein synthesis
inhibition of RNA and DNA
interference of metabolism within the cell
increase in WBCs
leukocytosis- nonspecific sign of infection
decrease in WBCs
neutropenia- impairs ability to attack foreign cells
Resistance to antibacterials
natural/ inherent resistance = without previous exposure to drug
Acquired resistance: caused by prior exposure to antibacterial
Nosocomial infections: infection acquired while patient is hospitalized. Many are due to drug-resistant bacteria.
Cross-resistance: can occur between antibacterial drugs that have similar actions
basic penicillins
introduced to kill staphylococcus
inhibit bacterial cell wall synthesis
narrow spectrum of activity
examples = penicillin G, procaine penicillin, penicillin V
Broad spectrum penicillins
active against gram positive and negative
also known as aminopenicillins
examples- amoxycillin (amoxil) = oral , Ampicillin (omnipen) = IV
Penicillinase resistant penicillins
used to treat penicillinase-producing S. aureus
also known as antistaphylococcal
examples = Nafcillin (unipen) and Oxacillin (Prostaphin)
Extended spectrum penicillins treat?
bone, joint, skin, soft tissue, respiratory tract, UTIs
much greater effect on gram negative organisms
extended spectrum- Antipseudomonal penicillins?
piperacillin-tazobactam (zosyn)- used to treat pseudomonas
penicillins- beta lactamase inhibitors
not given alone; commonly given with penicillinase-sensitive penicillins
examples:
-amoxicillin-clavulanic (augmentin)
-ampicillin-sulbactam (unasyn)
-piperacillin-tazobactam (zosyn)
Cephalosporins defined
also a beta lactum structure
-semi syntheitc
inhibit bacterial cell wall synthesis
bactericidal
Treat- respiratory, urinary, skin, bone, joint, genital infections
1st generation cephalosporins (gram positive)
Cefazolin sodium (ancef)
Cephalexin (keflex)
2nd generation cephalosporins(gram positive and negative)
cefoxitin sodium (mefoxin)
cefuroxime (ceftin, zinacef)
3rd generation cephalosporins (gram positive and negative)
ceftazidime (fortaz)
ceftriaxone (rocephin) - most common for bacterial pneumonia
Cephalosporins drug interactions
Alcohol: may cause flushing, dizziness, headache, nausea, vomiting, muscle cramps,
uricosurics: decreases excretion
contraceptives: may need back up birth control, may render contraceptives to be ineffective
Cephalosporins teaching
assess allergy, renal & liver function
-monitor for super infection: diarrhea may indicate C-diff infection
-counsel patients of use of back up oral contraceptives
Macrolides (Erythromycin) action
Binds to 50S ribosomal subunits & inhibits protein synthesis
Broad spectrum
Most gram +, some gram - bacteria
Bacteriostatic: low to moderate doses
Bactericidal: high doses
Oral or IV
Macrolides (Erythromycin) uses
Moderate to severe infections
Respiratory, GI tract, skin, and soft tissue infection
Treat mycoplasmal pneumoniae, Legionnaire's disease
Macrolides (Erythromycin) side effects
Side effects/adverse reactions
-GI distress, tinnitus
-Superinfection
-Ototoxicity, hepatotoxicity
Examples
-Erythromycin (E-Mycin)
-Clarithromycin (Biaxin, Biaxin XL)
-Azithromycin (Zithromax)
Macrolides interaction
-Levels of warfarin, theophylline, carbamazepine increase
-Erythromycin levels increase with fluconazole (Diflucan), ketoconazole (nizoral)
-Risk of sudden cardiac death
Azithromycin levels may be reduced by antacids
Macrolides Nursing Interventions
-Culture and sensitivity before therapy
-Monitor liver enzymes
-Advise client to take full regimen
-Administer antacids 1 hrs before or 2 hrs after macrolides
-Give azithromycin 1 hr before or 2 hrs after meals with full glass of water
Lincosamides action
Inhibit bacterial protein synthesis
Fight gram + staph aureus
Bacteriostatic and bactericidal
-Dependent upon dosage
Examples
-Clindamycin (Cleocin)
-Lincomycin (Lincocin)
Lincosamides Side effects/adverse reactions and drug interactions
Rash, GI distress, colitis, Anaphylactic shock

Drug interactions
-Kaolin and pectin decrease lincomycin absorption
-Tubocurarine and pancuronium may enhance
-neuromuscular blockade
Vancomycin (Vancocin) Action
Trough <20
Oral or IV
Inhibits cell wall synthesis
Fights gram +, staph aureus
Bactericidal
Uses
-Serious infections of bone, skin, lower respiratory tract
vancomycin (vancocin) adverse effects
nephrotoxic above 20meq/ml
"red man syndrome", hypotension, face and neck flushing; suprainfection
---VRE, if used for c-diff before other antibiotics= creates resistance
Vancomycin (Vancocin) Interventions
Nursing interventions
Culture and sensitivity prior to therapy
Monitor vancomycin levels
Administer over 1-2 hrs IV, rotate sites
Monitor BP, renal function, superinfection,
hearing, IV site
Tetracycline Action
Route
Oral, IM, IV

Inhibits protein synthesis
Broad spectrum
Fights gram + and - bacteria
Fights Helicobacter pylori
Treats acne (oral, topical)
Bacterial resistance
Route
Oral, IM, IV
Tetracyclines side effects
Discoloration and inadequate calcification of primary teeth of fetus if taken during pregnancy
or early childhood (under 8yo).
Phototoxic Reactions (sunburn type of reaction to sun)
Blood dyscrasia, superinfection
Pseudomembranous colitis, CNS toxicity
Hepatotoxicity
Nephrotoxicity in high doses
Tetracyclines types
Short-acting - Tetracycline (Achromycin)
Intermediate-acting - Demeclocycline
(Declomycin)
Long-acting - Doxycycline (Vibramycin)
May be taken with milk products and food
Tetracyclines Drug/food interactions
AVOID Milk products, antacids
Decreases effects of oral contraceptives
Digoxin absorption is increased, leading to
toxicity
Aminoglycosides
Action
-Inhibit bacterial protein synthesis
-Gram -, E. coli, Proteus pseudomonas,
-Bactericidal
Drugs
-Streptomycin
-Gentamicin (Garamycin), kanamycin (kantrex),
tobramycin (Nebcin)
Route
-IM, IV
Aminoglycosides side effects/interactions
Side effects/adverse reactions
Photosensitivity
Superinfection
Ototoxicity
Nephrotoxicity
Drug interactions
Penicillins decrease aminoglycoside effectiveness
Penicillins increase warfarin's effect
Fluoroquinolones -floxacin
Routes: oral, IV
Drugs: Ciprofloxacin (Cipro) - UTI
Levofloxacin (Levaquin) - UTI if close to sepsis


Side effects/adverse effects
-GI upset, rash, urticaria, tinnitus,
photosensitivity
-Superinfection
-Hematuria, crystalluria
-Psudomembranous colitis
Which nursing intervention has the highest priority for the patient who is taking cefepime (Maxipime)?
(4th generation cephalosporin)
monitor patient for s/s of superinfection
Sulfonamides
Action
-Inhibit bacterial synthesis of folic acid
-Bacteriostatic
-Fights gram - bacteria
--Proteus, Klebsiella, E. coli, Chlamydia
Uses
-Otitis media, respiratory infections
-UTIs, prostatitis, gonorrhea
Route
-Oral, IV, topical, ophthalmic
Fluoroquinolones -floxacin interactions
Levofloxacin increase effect of oral hypoglycemics

Antacids decrease absorption rate, theophylline, caffeine
Sulfonamides types
Short-acting
-Sulfisoxazole (Gantrisin)
Intermediate-acting
-Sulfamethoxazole (Gantanol)
-Trimethoprim-sulfamethoxazole (Bactrim
Sulfonamides TMP/SMZ
TMP/SMZ
Brand Names: Bactrim, Septra
Blocks bacterial protein synthesis
Bactericidal effect
Treats UTI, otitis media, bronchitis, pneumonia, burns
Route
Oral, IV
Sulfonamides side effects
Avoid 3rd trimester and Antacids
Causes photo sensitivity and Stevens-Johnson

Side effects/adverse reactions
-GI distress, stomatitis, photosensitivity
-Crystalluria, renal failure
-Blood dyscrasias, Stevens-Johnson syndrome
Nursing interventions
-Increase fluid intake
-Monitor renal function, CBC
-Monitor for rash, superinfection
-Avoid during third trimester
-Avoid antacids
Sulfonamides TMP/SMZ Interactions
Warfarin
-Increases anticoagulation
Oral hypoglycemic
-Increases hypoglycemia
A patient enters the emergency department with a draining wound. Once the patient is admitted and assessed, the priority nursing intervention is to
culture the wound
Which statement will the nurse include when teaching a patient about cephalosporin therapy?
inform your HCP if you develop mouth ulcers
A patient asks the nurse why she gets yeast infections after a course of antibiotics. The nurse explains,
Yeast infections are common when the normal body flora are disrupted
A patient is admitted to the health care facility with methicillin-resistant Staphylococcus aureus (MRSA). The nurse anticipates administration of which drug?
vancomycin (vancocin)
Sets with similar terms