Antibacterials Flashcards
What is the goal & outcome of antibacterial therapy?
Goal of therapy: kill bacteria or prevent their reproduction without harming the patient
Outcome: Disappearance of s/sx of infection
E.g. WBC between 5,000 and 10,000; no redness or drainage of wound, normal body temperature
General adverse reactions to antibacterials
- Allergic reactions (hypersensitivity or anaphylaxis)
- Superinfection
- Organ toxicity
Secondary infections that occur when too many host flora are killed by an antibiotic.
Host flora prevent growth of pathogenic organisms
Pathogenic microorganisms have chance to multiply
S/sx include diarrhea, bladder pain, painful urination, or abnormal vaginal discharge
Superinfections
Infections that take advantage of suppressed immune system
opportunistic infections
C. Diff is a bacteria that can cause severe diarrhea and colitis (which is inflammation of the colon). How does it spread?
C. diff spreads when people touch food, surfaces, or objects that are contaminated with feces (poop) from a person who has C. diff.
Do antibiotics only kill bad bacteria?
No. Antibiotics kill both good and bad bacteria.
Antibiotics effective against many gram + and gram – organisms organisms
Broad spectrum antibiotics
Antibiotics that primarily act against a single organism or a limited group of organisms
Narrow spectrum antibiotics
Why should we do a C&S before starting antibiotics
Aculture is atestto find microorganism responsible for causing an infection.
Asensitivity testchecks to see what kind of medicine, such as an antibiotic, will work best to treat the illness or infection.
How long does it take for bacteria be seen in culture?
Most bacteria can be seen in culture in 2-3 days (could take 10 days or longer)
Broad-spectrum antibiotics may be started before lab culture completed
Major Classes of Antibiotics by Pharmacologic Classification
Penicillins (ends with cillin)
Cephalosporins (starts with cef or ceph)
Macrolides (ends with mycin or micin)
Glycopeptides
Tetracyclines (ends with cycline)
Aminoglycosides (ends with mycin or micin)
Fluoroquinolones (ends with floxacin)
Sulfonamides (starts with sulf)
Bactericidal
Most widely effective
Least toxic
Major side effect: allergy
Penicillin
Side effects & adverse effects of penicillin
Side effects: NVD, pain at injection site
Adverse effects: bacterial resistance, allergic reaction, anaphylaxis, Clostridium difficile-associated diarrhea
What drugs are given to protect the beta-lactam antibiotic (penicillin) from being destroyed?
Don’t have antimicrobial action
Beta-lactamase inhibitors
Ex: Amoxicillin-clavulanic acid (Augmentin), Ampicillin-sulbactam (Unasyn), Piperacillin-tazobactam (Zosyn), Ticarcillin-clavulanic acid (Timentin)
Nursing interventions for penicillin
-Obtain C & S specimen
-Monitor for evidence of superinfection, especially in patients taking high doses of an antibiotic for a prolonged time.
-Examine the patient for an allergic reaction, especially after the 1st and 2nd doses.
-Instruct patient to take complete course of treatment.
3rd generation cephalosporin
Ceftiaxone (Rocephin)
Side effects & adverse effects of ceftiaxone (Rocephin)
Side effects: GI distress (nausea, vomiting, diarrhea), Alteration in blood clotting (increased bleeding)
Adverse effects: Nephrotoxicity, Stevens-Johnson syndrome, Anaphylaxis, Thrombocytopenia
Ceftiaxone (Rocephin) drug interactions
Alcohol
May cause disulfiram-like reaction
Flushing, dizziness, headache, nausea, vomiting, and muscular cramps
Disulfiram (also called Antabuse) is given to people who chronically drink alcohol- it causes an acute reaction when the person drinks alcohol after taking this drug
Nursing interventions for Ceftiaxone (Rocephin)
-C & S prior to starting antibiotic
-Tell patient to report signs of superinfection.
-Instruct patient to take complete course of treatment.
-Observe for hypersensitivity reactions.
-Advise patient to take medication with food if gastric irritation occurs.
Penicillin substitute
Used if pt has a hypersensitivity to penicillin
Macrolides
Ex: Azithromycin
Side effects of Macrolides
GI distress including nausea, vomiting, diarrhea, cramping
Photosensitivity
Headache, fatigue, dizziness
Oral candidiasis
Adverse effects of Macrolides
Anaphylaxis
Superinfection
Hepatotoxicity (use with caution in patients with hepatic dysfunction)
Stevens-Johnson syndrome
Blood dyscrasias
Nursing interventions for Macrolides
Obtain a sample for C&S testing before starting antibiotic.
Monitor the patient for liver damage.**
Administer antacids either 2 hours before or 2 hours after taking**
Encourage patient to report side effects/adverse effects.
Tell patient to report onset of loose stools/diarrhea (c-diff)**
Drugs used to treat MRSA, pseudomembranous colitis caused by clostridium difficile
Dosing may be based on peak & trough levels
Glycopeptides
Ex: Vancomycin
Side effects of Glycopeptides
GI symptoms (nausea, vomiting)
Dizziness
Superinfection
Disulfiram-like reaction to alcohol
Adverse reactions of Glycopeptides
Ex: Vancomycin
Ototoxicity**
Nephrotoxicity**
Anaphylaxis
Blood dyscrasias
Stevens-Johnson syndrome
Clostridium difficile-associated diarrhea
S/sx of adverse reaction of Glycopeptides
Ex: Vancomycin
Occurs when IV too rapid
Severe hypotension
Red blotching of face, neck, chest, extremities
Toxic reaction not allergic reaction
Nursing interventions for Vanco
Check C&S before therapy
Monitor vancomycin levels**
Administer over 1 to 2 hours IV**
Monitor BP**
Monitor renal function tests (BUN and creatinine) and hearing**
Monitor patient for superinfection
Tetracyclines prototype
Doxycycline
Side effects of Tetracyclines
Nausea and vomiting
Diarrhea
Photosensitivity (severe burns)
Discoloration or hypopolasia of teeth and temporary stunting of growth
Do not give to children younger than 8 years.
Stomatitis, glossitis
Adverse effects of Tetracyclines
Anaphylaxis
Clostridium difficile-associated diarrhea
Ototoxicity, hepatotoxicity, nephrotoxicity
CNS toxicity
Pancytopenia, Stevens-Johnson syndrome
Drug/food interactions for Tetracyclines
Milk products (decreased absorption)
Antacids
Oral contraceptives
Penicillins
Aminoglycosides
Nursing interventions for Tetracyclines
Check C&S before drug
Monitor kidney and liver function.**
Take on an empty stomach and full glass of water **
Advise patient to use sunscreen (photosensitivity)**
Teach patient to report superinfection.
Warn patient to avoid milk, iron, antacids (interfere with absorption).**
Recommend that the patient use a non-hormonal birth control method in addition to OCP’s (to reduce risk of pregnancy and is also Class D medication)**
Aminoglycosides prototype
Gentamycin
Side effects of Aminoglycosides
Photosensitivity
Superinfection
Stomatitis
Nausea, vomiting
Fever
Lethargy
Adverse effects of Aminoglycosides
Anaphylaxis
Seizures
Ototoxicity
Nephrotoxicity
Clostridium difficile–associated diarrhea
Stevens-Johnson syndrome
Nursing interventions for Aminoglycosides
-Check C&S.
-Check for hearing loss and renal function.**
-Check that therapeutic drug monitoring has been ordered for Peak & Trough drug levels.**
-Monitor for s/sx of superinfection
Sulfonamide prototype
Trimethoprim-Sulfamethoxazole (Bactrim, Septral)
Why are both drugs, Trimethoprim- Sulfamethoxazole, used together in one compound?
cause bacterial resistance to develop much more slowly.
Side effects/adverse effects of Trimethoprim-Sulfamethoxazole
GI distress, stomatitis, photosensitivity
Crystalluria, renal failure
Blood dyscrasias, Stevens-Johnson syndrome
Nursing interventions for Trimethoprim-Sulfamethoxazole
Increase fluid intake to at least 2000 mL/day.**
Monitor CBC and renal function.**
Monitor for rash, superinfection.
Avoid during third trimester.**
Avoid antacids**
Monitor for sore throat, bruising, bleeding**
Teach patient to avoid direct sunlight**
Fluroquinolones prototype
Ciprofloxacin (Cipro)
Side effects of Fluroquinolones
Rash, nausea, headache, abdominal pain, vomiting, dizziness, changes in taste, sleep disturbances, photosensitivity
Adverse effects of Fluroquinolones
Serious heart dysrhythmias (esp. when taken with other drugs), neurotoxicity, Stevens-Johnson syndrome, changes in blood glucose level, tendon rupture, peripheral neuropathy
Drug interactions for Fluroquinolones
Antacids decrease absorption rate.
May increase effect of oral hypoglycemics
Nursing interventions for Fluroquinolones
Check C&S.
Monitor heart rate and rhythm**
Infuse IV over 60 to 90 minutes.**
Increase fluid intake to more than 2000 mL/d. **
Tell patient to avoid caffeine.**
Check for superinfection
Teach patient to stop drug and notify prescriber of any tendon or joint pain/swelling**
Monitor blood glucose**
Combo antibiotics should be reserved for
specific uncontrolled infections
When two antibiotics are combined, the result may be additive, potentiative, or antagonistic
Additive- effect is equal to the sum of the effects of two antibiotics
Potentiative- effect occurs when one antibiotic potentiates the effect of the second, increasing its effectiveness
Antagonistic- when two drugs are used together and the desired effect is reduced
When a bactericidal (like penicillin) and a bacteriostatic (tetracycline) are used together, the effect is greatly
reduced
Antibacterial resistance is caused by
overused, overprescribed, improperly taken antibacterial drugs
General take-home points
Finish medication to prevent superinfection
Decreases oral contraception effectiveness in amoxycillin, doxycycline
No alcohol- antibiotics can harm the liver
Take on an empty stomach and full glass of water with azithromycin (macrolides), doxycycline (tetracycline), levofloxacin (fluoroquinolones)
No sun with levofloxacin (fluoroquinolones), doxycycline (tetracyclines), sulfa drugs (Bactrim)
Vancomycin, gentamycin, neomycin- very toxic to kidneys and ears
Take amoxicillin with food to decrease GI symptoms and increase absorption
Vanco is incompatible with a lot of IV drugs, so be careful when infusion
