Pharmacology
ESSAY BOUT THE MOST CONTAGIOUS DISEASES AND ITS PHARMACOLOGICAL MANAGEMENT.
( MEANING THE MOST MEDICATION USED IN THE MOST CONTAGIOUS DISEASES)
Chapter 38
Antibiotics Part 1
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Community-associated infections
An infection that is acquired by a person who has not been hospitalized or had a medical procedure (such as dialysis, surgery, catheterization) within the past year
Infections: Sites of Origin
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Health care–associated infections
Contracted in a hospital or institutional setting
Were not present or incubating in the patient on admission to the facility
More difficult to treat because causative microorganisms are often drug resistant and the most virulent
Occur in 10% of hospitalized patients
MRSA most common
Previously known as nosocomial
Infections: Sites of Origin (cont’d)
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Handwashing
Antiseptics
Disinfectants
Health Care–Associated Infections: Prevention
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Disinfectant
Kills organisms
Used only on nonliving objects
Antiseptic
Generally only inhibits the growth of microorganisms but does not necessarily kill them
Applied exclusively to living tissue
Health Care–Associated Infections: Prevention (cont’d)
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Medications used to treat bacterial infections
Ideally, before beginning antibiotic therapy, the suspected areas of infection should be cultured to identify the causative organism and potential antibiotic susceptibilities
Antibiotics
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Empiric therapy: treatment of an infection before specific culture information has been reported or obtained
Definitive therapy: antibiotic therapy tailored to treat organism identified with cultures
Prophylactic therapy: treatment with antibiotics to prevent an infection, as in intraabdominal surgery or after trauma
Antibiotic Therapy
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Therapeutic response
Decrease in specific signs and symptoms of infection are noted (fever, elevated WBC, redness, inflammation, drainage, pain)
Subtherapeutic response
Signs and symptoms of infection do not improve
Antibiotic Therapy (cont’d)
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Superinfection
Pseudomembranous colitis
Secondary infection
Resistance
Food-drug interactions
Host factors
Allergic reactions
Antibiotic Therapy (cont’d)
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Sulfonamides
Penicillins
Cephalosporins
Macrolides
Quinolones
Aminoglycosides
Tetracyclines
Antibiotics: Classes
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Interference with cell wall synthesis
Interference with protein synthesis
Interference with DNA replication
Acting as a metabolite to disrupt critical metabolic reactions inside the bacterial cell
Antibiotic Therapy:
Mechanism of Action
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Bactericidal: kill bacteria
Bacteriostatic: inhibit growth of susceptible bacteria, rather than killing them immediately; will eventually lead to bacterial death
Actions of Antibiotics
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One of the first groups of antibiotics
Often combined with another antibiotic
Sulfamethoxazole combined with trimethoprim (a nonsulfonamide antibiotic), known as Bactrim, Septra, or co-trimoxazole and often abbreviated as SMX-TMP, is used commonly in clinical practice
Antibiotics: Sulfonamides
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Bacteriostatic action
Prevent synthesis of folic acid required for synthesis of purines and nucleic acid
Do not affect human cells or certain bacteria—they can use preformed folic acid
Only affect organisms that synthesize their own folic acid
Sulfonamides:
Mechanism of Action
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Effective against both gram-positive and gram-negative bacteria
Treatment of UTIs caused by susceptible strains of:
Enterobacter spp., Escherichia coli, Klebsiella spp., Proteus mirabilis, Proteus vulgaris, Staphylococcus aureus
Sulfonamides: Indications
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Pneumocystis jirovecii pneumonia (PJP)
Co-trimoxazole
Upper respiratory tract infections
Sulfamethoxazole/trimethoprim is commonly used for outpatient Staphylococcus infections, due to the high rate of community-acquired MRSA infections
Sulfonamides: Indications (cont’d)
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Body System Adverse Effects
Blood Hemolytic and aplastic anemia, agranulocytosis, thrombocytopenia
Integumentary Photosensitivity, exfoliative dermatitis, Stevens-Johnson syndrome, epidermal necrolysis
Sulfonamides:
Adverse Effects
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Body System Adverse Effects
GI Nausea, vomiting, diarrhea, pancreatitis
Other Hepatotoxicity, convulsions, crystalluria,
toxic nephrosis, headache, peripheral neuritis, urticaria, cough
Sulfonamides:
Adverse Effects (cont’d)
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Penicillins
Cephalosporins
Carbapenems
Monobactams
Beta-Lactam Antibiotics
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Natural penicillins
Penicillinase-resistant penicillins
Aminopenicillins
Extended-spectrum penicillins
Penicillins
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Natural penicillins
penicillin G
penicillin V
Penicillinase-resistant drugs
nafcillin
cloxacillin
oxacillin
dicloxacillin
Penicillins (cont’d)
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Aminopenicillins
amoxicillin (Amoxil), ampicillin (generic only)
Extended-spectrum drugs
carbenicillin
piperacillin
ticarcillin
Penicillins (cont’d)
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Penicillins enter the bacteria via the cell wall
Inside the cell they bind to penicillin-binding protein
Once bound, normal cell wall synthesis is disrupted
Result: bacteria cells die from cell lysis
Penicillins do not kill other cells in the body
Penicillins: Mechanism of Action
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Prevention and treatment of infections caused by susceptible bacteria, such as:
Gram-positive bacteria, including Streptococcus spp., Enterococcus spp., Staphylococcus spp.
Penicillins: Indications
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Allergic reactions to the penicillins occur in 0.7% to 4% of treatment courses
Urticaria, pruritus, angioedema
Those allergic to penicillins have an increased risk of allergy to other beta-lactam antibiotics
Only those patients with a history of throat swelling or hives from penicillin should not receive cephalosporins
Penicillins: Adverse Effects
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Common adverse effects
Nausea, vomiting, diarrhea, abdominal pain
Other adverse effects are less common
Penicillins: Adverse Effects (cont’d)
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MANY interactions!
NSAIDs
Oral contraceptives
Warfarin
Others
Penicillins: Interactions
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Classroom Response Question
A patient is receiving Augmentin (amoxicillin and clavulanic acid) liquid solution through a PEG tube. What is the purpose of the clavulanic acid?
It works synergistically with the antibiotic to improve potency.
It inhibits the action of the enzymes produced by beta-lactamase–producing bacteria.
It protects the antibiotic from the harmful gastric acid secretions in the stomach.
It enhances the absorption of the antibiotic in the small intestine.
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Correct answer: B
Rationale: The clavulanic acid works to inhibit the action of the enzymes produced by the bacteria, which would normally inactivate the antibiotic.
First generation
Second generation
Third generation
Fourth generation
Fifth generation
Cephalosporins
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Semisynthetic antibiotics
Structurally and pharmacologically related
to penicillins
Bactericidal action
Broad spectrum
Divided into groups according to their antimicrobial activity
Cephalosporins (cont’d)
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Good gram-positive coverage
Poor gram-negative coverage
Parenteral and PO forms
Examples
cefadroxil (Duricef, Ultracef)
cephradine (Velosef)
cefazolin (Ancef)
cephalexin (Keflex)
Cephalosporins:
First Generation
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Used for surgical prophylaxis, and for susceptible staphylococcal infections
cefazolin (Ancef and Kefzol): IV or IM
cephalexin (Keflex): PO
Cephalosporins:
First Generation (cont’d)
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Good gram-positive coverage
Better gram-negative coverage than first generation
Examples:
cefaclor (Ceclor)
cefprozil (Cefzil)
cefoxitin (Mefoxin)
cefuroxime (Zinacef)
cefotetan (Cefotan)
Cephalosporins:
Second Generation
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cefoxitin (Mefoxin): IV and IM
Used prophylactically for abdominal or colorectal surgeries
Also kills anaerobes
cefuroxime
Zinacef is parenteral form; Ceftin is PO
Surgical prophylaxis
Does not kill anaerobes
Cephalosporins:
Second Generation (cont’d)
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Most potent group against gram-negative bacteria
Less active against gram-positive bacteria
Examples
cefotaxime (Claforan)
ceftazidime (Fortaz)
cefdinir (Omnicef)
ceftizoxime (Cefizox)
ceftriaxone (Rocephin)
Cephalosporins:
Third Generation
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ceftriaxone (Rocephin)
IV and IM, long half-life, once-a-day dosing
Elimination is primarily hepatic
Easily passes meninges and diffused into CSF to treat CNS infections
Cephalosporins:
Third Generation (cont’d)
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ceftazidime (Ceptaz, Fortaz, Tazidime)
IV and IM forms
Excellent gram-negative coverage
Used for difficult-to-treat organisms such as Pseudomonas spp.
Excellent spectrum of coverage
Resistance is limiting usefulness
Cephalosporins:
Third Generation (cont’d)
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Broader spectrum of antibacterial activity than third generation, especially against gram-positive bacteria
Uncomplicated and complicated UTI
cefepime (Maxipime)
Cephalosporins:
Fourth Generation
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ceftaroline (Teflaro)
Broader spectrum of antibacterial activity
Effective against a wide variety of organisms
MRSA
Cephalosporins:
Fifth Generation
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Similar to penicillins
Mild diarrhea, abdominal cramps, rash, pruritus, redness, edema
Potential cross-sensitivity with penicillins if allergies exist
Cephalosporins:
Adverse Effects
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Broadest antibacterial action of any antibiotics to date
Reserved for complicated body cavity and connective tissue infections in acutely ill hospitalized patients
May cause drug-induced seizure activity
This risk can be reduced with proper dosage
Carbapenems
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imipenem/cilastatin (Primaxin)
Used for treatment of bone, joint, skin, and soft-tissue infections; many other uses
Cilastatin inhibits an enzyme that breaks down imipenem
meropenem (Merrem)
ertapenem (Invanz)
doripenem (Doribax)
Carbapenems
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aztreonam (Azactam)
Synthetic beta-lactam antibiotic
Primarily active against aerobic gram-negative bacteria (E. coli, Klebsiella spp., Pseudomonas spp.)
Bactericidal
Parenteral use only
Used for moderately severe systemic infections and UTIs
Monobactams
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erythromycin (E-mycin, E.E.S, others)
azithromycin (Zithromax)
clarithromycin (Biaxin)
Macrolides
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Prevent protein synthesis within bacterial cells
Considered bacteriostatic
Bacteria will eventually die
In high enough concentrations, may also be bactericidal
Macrolides:
Mechanism of Action
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Strep infections
Streptococcus pyogenes (group A beta-hemolytic streptococci)
Mild to moderate URI and LRI
Haemophilus influenzae
Spirochetal infections
Syphilis and Lyme disease
Gonorrhea, Chlamydia, Mycoplasma
Macrolides: Indications
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azithromycin and clarithromycin
Approved for Mycobacterium avium-intracellulare complex infection (opportunistic infection associated with HIV/AIDS)
clarithromycin
Recently approved for use in combination with omeprazole for treatment of active ulcer disease associated with Helicobacter pylori infection
Macrolides: Indications (cont’d)
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GI effects, primarily with erythromycin
Nausea, vomiting, diarrhea, hepatotoxicity, flatulence, jaundice, anorexia
Azithromycin and clarithromycin: fewer GI adverse effects, longer duration of action, better efficacy, better tissue penetration
Macrolides: Adverse Effects
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telithromycin (Ketek)
Only drug in this class
Better antibacterial coverage than macrolides
Associated with severe liver disease
Use is limited
Ketolide
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demeclocycline (Declomycin)
oxytetracycline (Terramycin)
tetracycline
doxycycline (Doryx, Vibramycin)
minocycline (Minocin)
tigecycline (Tygacil)
Tetracyclines
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Natural and semisynthetic
Obtained from cultures of Streptomyces
Bacteriostatic—inhibit bacterial growth
Inhibit protein synthesis
Stop many essential functions of the bacteria
Tetracyclines (cont’d)
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Bind (chelate) to Ca+++ and Mg++ and Al+++ ions to form insoluble complexes
Dairy products, antacids, and iron
salts reduce oral absorption of tetracyclines
Should not be used in children under age 8 or in pregnant/lactating women because tooth discoloration will occur if the drug binds to the calcium in the teeth
Tetracyclines (cont’d)
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Wide spectrum
Gram-negative and gram-positive organisms, protozoa, Mycoplasma, Rickettsia, Chlamydia, syphilis, Lyme disease, acne, others
Demeclocycline is also used to treat SIADH by inhibiting the action of ADH
Tetracyclines: Indications
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Strong affinity for calcium
Discoloration of permanent teeth and tooth
enamel in fetuses and children, or nursing infants if taken by the mother
May retard fetal skeletal development if taken during pregnancy
Tetracyclines: Adverse Effects
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Alteration in intestinal flora may result in:
Superinfection (overgrowth of nonsusceptible organisms such as Candida)
Diarrhea
Pseudomembranous colitis
Tetracyclines: Adverse Effects (cont’d)
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May also cause:
Vaginal candidiasis
Gastric upset
Enterocolitis
Maculopapular rash
Other effects
Tetracyclines: Adverse Effects (cont’d)
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Before beginning therapy, assess drug allergies; renal, liver, and cardiac function; and other lab studies
Be sure to obtain thorough patient health history, including immune status
Assess for conditions that may be contraindications to antibiotic use or that may indicate cautious use
Assess for potential drug interactions
Nursing Implications
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It is ESSENTIAL to obtain cultures from appropriate sites BEFORE beginning antibiotic therapy
Nursing Implications (cont’d)
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Instruct patients to take antibiotics exactly as prescribed and for the length of time prescribed; they should not stop taking the medication early when they feel better
Assess for signs and symptoms of superinfection: fever, perineal itching, cough, lethargy, or any unusual discharge
Nursing Implications (cont’d)
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For safety reasons, check the name of the medication carefully because there are many drugs that sound alike or have similar spellings
Nursing Implications (cont’d)
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Classroom Response Question
When completing an admission assessment, the patient states that she is allergic to sulfa drugs. What will the nurse do next?
Mark the allergy on her medical record.
Place an “allergy” armband on the patient.
Ask the patient for more information about the allergic reaction she had.
Notify the physician about the patient’s allergy.
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Correct answer: C
Rationale: Some patients will say they are “allergic” to drugs when in fact what they experienced was a common and mild adverse effect. The nurse should clarify the patient’s statements with open-ended questions.
Each class of antibiotics has specific adverse effects and drug interactions that must be carefully assessed and monitored
The most common adverse effects of antibiotics are nausea, vomiting, and diarrhea
All oral antibiotics are absorbed better if taken with at least 6 to 8 ounces of water
Nursing Implications (cont’d)
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Classroom Response Question
A patient has a prescription for a sulfa drug as treatment for a urinary tract infection. She is also taking an oral contraceptive, an oral sulfonylurea antidiabetic drug, and phenytoin for a history of seizures. Which drug may pose a potential serious interaction with the sulfa drug?
The oral contraceptive
The oral antidiabetic drug
The phenytoin
All of these
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Correct answer: D
Rationale: The combination of the sulfa drug with the oral contraceptive may reduce the effectiveness of the contraceptive. The combination with the oral antidiabetic drug may potentiate the hypoglycemic effect of the sulfonylurea drug, while the combination with the phenytoin may potentiate the toxic effects of the phenytoin.
Sulfonamides
Take with 2000 to 3000 mL of fluid/24 hr
Assess RBCs prior to beginning therapy
Take oral doses with food
Nursing Implications (cont’d)
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Penicillins
Take oral doses with water (not juices) as acidic fluids may nullify drug’s antibacterial action
Monitor patients taking penicillin for an allergic reaction for at least 30 minutes after administration
Nursing Implications (cont’d)
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Cephalosporins
Assess for penicillin allergy; may have cross allergy
Give orally administered forms with food to decrease GI upset, even though this will delay absorption
Some of these drugs may cause a disulfiram (Antabuse)-like reaction when taken with alcohol
Nursing Implications (cont’d)
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Macrolides
These drugs are highly protein-bound and will cause severe interactions with other protein-bound drugs
The absorption of oral erythromycin is enhanced when taken on an empty stomach, but because of the high incidence of GI upset, many drugs are taken after a meal or snack
Nursing Implications (cont’d)
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Tetracyclines
Avoid milk products, iron preparations, antacids, and other dairy products because of the chelation and drug-binding that occurs
Take all medications with 6 to 8 ounces of fluid, preferably water
Because of photosensitivity, avoid sunlight and
tanning beds
Nursing Implications (cont’d)
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Monitor for therapeutic effects
Improvement of signs and symptoms of infection
Return to normal vital signs
Negative culture and sensitivity tests
Disappearance of fever, lethargy, drainage, and redness
Monitor for adverse reactions
Nursing Implications (cont’d)
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Chapter 39
Antibiotics Part 2
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Multidrug resistance
Therapeutic drug monitoring
Minimum inhibitory concentration (MIC)
Time-dependent killing
Concentration-dependent killing
Once-daily dosing vs. multidaily dosing
Peak and trough blood levels
Synergistic effects
Postantibiotic effect (PAE)
Antibiotic Therapy: Concepts
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Organisms that are resistant to one or more classes of antimicrobial drugs
Methicillin-resistant Staphylococcus aureus (MRSA)
Vancomycin-resistant Enterococcus (VRE)
Organisms producing extended-spectrum beta-lactamases (ESBLs)
Organisms producing Klebsiella pneumoniae carbapenemase (KPC)
Multidrug-Resistant Organisms
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Natural and semisynthetic
Produced from Streptomyces
Poor oral absorption; no PO forms (exception neomycin)
Very potent antibiotics with serious toxicities
Bactericidal; prevent protein synthesis
Kill mostly gram-negative bacteria; some
gram-positive
Aminoglycosides
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gentamicin
neomycin (Neo-fradin)
tobramycin (TOBI)
amikacin
Aminoglycosides (cont’d)
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Used to kill gram-negative bacteria, such as Pseudomonas spp., Escherichia coli, Proteus spp., Klebsiella spp., Serratia spp.
Often used in combination with other antibiotics for synergistic effects
Used for certain gram-positive infections that are resistant to other antibiotics
Aminoglycosides: Indications
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Aminoglycosides are poorly absorbed through the GI tract, and given parenterally
Exception: neomycin
Given orally to decontaminate the GI tract before surgical procedures
Also used as an enema for this purpose
Used to treat hepatic encephalopathy
Aminoglycosides: Indications (cont’d)
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Cause serious toxicities
Nephrotoxicity (renal damage)
Ototoxicity (auditory impairment and vestibular impairment [eighth cranial nerve])
Must monitor drug levels to prevent toxicities
Minimum inhibitory concentration (MIC)
Aminoglycosides: Adverse Effects
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Ototoxicity and nephrotoxicity are the most significant
Headache
Paresthesia
Fever
Superinfections
Vertigo
Skin rash
Dizziness
Aminoglycosides:
Adverse Effects (cont’d)
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Also called fluoroquinolones
Excellent oral absorption
Absorption reduced by antacids
Effective against gram-negative organisms and some gram-positive organisms
Quinolones
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ciprofloxacin (Cipro)
norfloxacin (Noroxin)
levofloxacin (Levaquin)
moxifloxacin (Avelox)
Quinolones (cont’d)
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Bactericidal
Alter DNA of bacteria, causing death
Do not affect human DNA
Quinolones:
Mechanism of Action
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Gram-negative bacteria such as Pseudomonas
Complicated urinary tract, respiratory, bone and joint, GI, skin, and sexually transmitted infections
Anthrax (ciproflaxin)
Quinolones: Indications
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Classroom Response Question
During intravenous quinolone therapy in an 88-year-old patient, which potential problem is of most concern when assessing for adverse effects?
Hepatotoxicity
Rhabdomyolysis
Tendon rupture
Nephrotoxicity
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Correct answer: C
Rationale: A black box warning is required by the U.S. Food and Drug Administration for all quinolones because of the increased risk of tendonitis and tendon rupture with use of the drugs. This effect is more common in elderly patients, patients with renal failure, and those receiving concurrent glucocorticoid therapy (e.g., prednisone).
Quinolones: Adverse Effects
Body System Adverse Effects
CNS Headache, dizziness, insomnia, depression, restlessness, convulsions
GI Nausea, vomiting, diarrhea, constipation, thrush, increased liver function studies, others
Cardiac Prolonged QT interval
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Quinolones:
Adverse Effects (cont’d)
Body System Adverse Effects
Integumentary Rash, pruritus, urticaria, flushing
Other Ruptured tendons,* tendonitis,* fever, chills, blurred vision, tinnitus
*Black box warning: Increased risk of tendonitis and tendon rupture
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clindamycin (Cleocin)
linezolid (Zyvox)
metronidazole (Flagyl)
nitrofurantoin (Macrodantin)
quinupristin/dalfopristin (Synercid)
daptomycin (Cubicin)
vancomycin (Vancocin)
colistimethate (Coly-Mycin)
telavancin (Vibativ)
Miscellaneous Antibiotics
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clindamycin (Cleocin)
Used for chronic bone infections, GU infections, intraabdominal infections, other serious infections
May cause pseudomembranous colitis (also known as antibiotic-associated colitis, Clostridium difficile diarrhea, or C. difficile infection)
Potential interaction with vecuronium
Miscellaneous Antibiotics (cont’d)
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linezolid (Zyvox)
New class: oxazolidinones
Used to treat vancomycin-resistant Enterococcus faecium (VREF, VRE), hospital-acquired, and skin structure infections, including those with MRSA
May cause hypotension, serotonin syndrome if taken with SSRIs, and reactions if taken with tyramine-containing foods
Miscellaneous Antibiotics (cont’d)
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Classroom Response Question
A patient is prescribed linezolid (Zyvox) to treat hospital-acquired pneumonia. It is most important for the nurse to determine if the patient is also taking which medication?
A diuretic
A selective serotonin reuptake inhibitor
A cardiac glycoside
A thyroid replacement drug
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Correct answer: B
Rationale: Linezolid has the potential to strengthen the vasopressor (prohypertensive) effects of various vasopressive drugs such as dopamine by an unclear mechanism. Also, there have been postmarketing case reports of this drug causing serotonin syndrome when used concurrently with serotonergic drugs such as the selective serotonin reuptake inhibitor (SSRI) antidepressants. It is recommended that the SSRI be stopped while the patient is receiving linezolid therapy if possible.
metronidazole (Flagyl)
Used for anaerobic organisms
Intraabdominal and gynecologic infections
Protozoal infections
Several drug interactions
Miscellaneous Antibiotics (cont’d)
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nitrofurantoin (Macrodantin)
Primarily used for urinary tract infections (UTIs) (E. coli, Staphylococcus aureus, Klebsiella spp., Enterobacter spp.)
Use carefully if renal function is impaired
Drug concentrates in the urine
May cause fatal hepatotoxicity
Miscellaneous Antibiotics (cont’d)
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quinupristin/dalfopristin (Synercid)
30:70 combination, work synergistically
Used for bacteremia and infections caused by vancomycin-resistant Enterococcus (VRE) and for treatment of complicated skin and skin structure infections caused by S. pyogenes and S. aureus, including MRSA
May cause arthralgias, myalgias
Miscellaneous Antibiotics (cont’d)
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vancomycin (Vancocin)
Treatment of choice for MRSA and other gram-positive infections
Oral vancomycin is indicated for the treatment of antibiotic-induced colitis (C. difficile) and for the treatment of staphylococcal enterocolitis
Must monitor blood levels to ensure therapeutic levels and prevent toxicity
May cause ototoxicity and nephrotoxicity
Miscellaneous Antibiotics (cont’d)
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Classroom Response Question
A 58-year-old man is receiving vancomycin as part of the treatment for a severe bone infection. After the infusion, he begins to experience some itching and flushing of the neck, face, and upper body. He reports no chills or difficulty breathing. The nurse should suspect:
an allergic reaction has occurred.
an anaphylactic reaction is about to occur.
the medication will not be effective for the bone infection.
the IV dose may have infused too quickly.
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Elsevier items and derived items © 2009, 2005, 2001 by Saunders, an imprint of Elsevier Inc.
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Correct answer: D
Rationale: These symptoms are know as red man syndrome and may occur during or after an infusion of vancomycin. This syndrome is characterized by flushing and/or itching of the head, face, neck, and upper trunk area. Symptoms can usually be alleviated by slowing the rate of infusion to at least 1 hour. Red man syndrome is bothersome but usually not harmful. Rapid infusions may also cause hypotension.
vancomycin (Vancocin) (cont’d)
Red man syndrome may occur
Flushing/itching of head, neck, face, upper trunk
Antihistamine may be ordered to reduce these effects
Additive neuromuscular blocking effects in patients receiving neuromuscular blockers
Should be infused over 60 minutes
Rapid infusions may cause hypotension
Miscellaneous Antibiotics (cont’d)
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daptomycin (Cubicin)
Only drug of the new class known as lipopeptides
Mechanism of action is not completely known
Binds to gram-positive cells in a calcium-dependent process and disrupts the cell membrane potential
Used to treat complicated skin and soft-tissue infections caused by susceptible gram-positive bacteria, including MRSA and VRE
Miscellaneous Antibiotics (cont’d)
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colistimethate (Coly-Mycin)
Polypeptide antibiotic that penetrates and disrupts the bacterial membrane of susceptible strains of gram-negative bacterial
Commonly referred to as colistin
Serious adverse effects
Can cause acute respiratory failure when administered by inhalation
Miscellaneous Antibiotics (cont’d)
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telavancin (Vibativ)
Lipoglycopeptide
Indicated for the treatment of skin and skin structure infections caused by susceptible gram-positive organisms
Effective against MRSA and VRE
Most common adverse effects include renal toxicity, infusion-related reactions, and QT prolongation
Miscellaneous Antibiotics (cont’d)
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Before beginning therapy, assess drug allergies; hepatic, renal, and cardiac function; and other lab studies
Be sure to obtain thorough patient health history, including immune status
Assess for conditions that may be contraindications to antibiotic use or that may indicate cautious use
Assess for potential drug interactions
Nursing Implications
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It is ESSENTIAL to obtain cultures from appropriate sites BEFORE beginning antibiotic therapy
Instruct patients to take antibiotics exactly as prescribed and for the length of time prescribed; they should not stop taking the medication early even if they feel better
Nursing Implications (cont’d)
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Assess for signs and symptoms of superinfection: fever, perineal itching, cough, lethargy, or any unusual discharge
For safety reasons, check the name of the medication carefully because there are many drugs that sound alike or have similar spellings
Nursing Implications (cont’d)
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Each class of antibiotics has specific adverse effects and drug interactions that must be carefully assessed and monitored
Nursing Implications (cont’d)
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Classroom Response Question
A group of office workers is concerned because a package was opened that contained a white powder substance. There is a concern that the white powder is anthrax. Which drug does the nurse anticipate being prescribed for the office workers?
daptomycin (Cubicin)
colistimethate (Coly-Mycin)
ciprofloxacin (Cipro)
quinupristin/dalfopristin (Synercid)
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Elsevier items and derived items © 2009, 2005, 2001 by Saunders, an imprint of Elsevier Inc.
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Correct answer: C
Rationale: Ciprofloxacin (Cipro) is the drug of choice for the treatment of anthrax (infection with Bacillus anthracis).
Monitor for therapeutic effects
Improvement of signs and symptoms of infection
Return to normal vital signs
Negative culture and sensitivity tests
Disappearance of fever, lethargy, drainage, and redness
Monitor for adverse reactions
Nursing Implications (cont’d)
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