Week 9: Antibiotic drugs Flashcards
gram positive
purple stain,
gram negative
red stain more difficult to treat because the drug molecules have a harder time penetrating he more complex cell walls
empirical therapy
antibiotic selected best to kill infection
prophylactic anitbiotic therapy
is used to prevent an infection
subtherapeutic
when signs and symptoms do not improve
superinfections
can occur when antibiotics reduce or completely eliminate the normal bacterail flora, which consists of certain fungi that are needed to maintain normal function in organs
coloured sputum
is one sign of a bacterial superinfection during a viral resp illness.
quinolone and antacids
resulting in decreased absorption of quinolones
children and tetracyclines, which affect developing teeth or bones,
fluoroquinolones which affect bone development in childrenand sulfonamides which may displace bilirubin from albumin.
penicillins and sulfonamides
are two broad classes of antibiotics to which many people have allergic reactions too
the four most common mechanisms of anitbiotic actions
are interferance with bacterial wall synthesis, interference with protein sunthesis, interferance with DNA and RNA. and something else that doesnt sound important
bacterial anitbiotics
can kill a wide variety of gram positive and negative bacteria
Antibiotic Resistance may occur by
> Production of drug-inactivating enzymes
Changes in receptor structure or drug permeation
Development of new metabolic pathways
Emergence of drug resistant microbes
Factors that Facilitate Development of Resistance
> Drug concentrations in tissues are too low
insufficient duration of therapy
prophylactic use
General Considerations for Selecting Antimicrobial Therapy
- Identify the pathogen
- Choose the right drug
- Drug spectrum – broad or narrow
Nosocomial Infection
A hospital-acquired infection
bactericidal
kill bacteria
bacteriostatic:
suppress growth of bacteria; effect is reversible if drug is removed (unless host’s defenses have removed the organism)
NARROW AND broad spectrum
May be effective against a few bacteria (_narrow spectrum) or effective against many types of bacteria (broad spectrum )
Narrow spectrum drugs limits the potential of a superinfection
For most acute infections, the average duration of treatment with an antibiotic is
7-10days.
If your client has renal insufficiency, the dose of the antibiotic may need to be _
lowered or the interval between doses may be increased as most antibiotics are excreted by the kidneys and some are nephrotoxic.
Antibiotics: Uses
1.Prevention OR
2.Treatment of
gram-positive or gram-negative bacterial infections
Antibiotics: Contraindications/Precautions
know drug allergy
preggo/lactation
renel or heptic dysfunction
Antibiotics: Interactions
Antacids—decreased absorption (give 2 hrs before or after antibiotics)
Oral contraceptives—effectiveness may be decreased
Alcohol—disulfiram reaction (metronidiazole)
Antibiotics: Adverse Effects
anorexia, nausea, vomiting, diarrhea
allergic reaction anaphylaxis—rash, wheezing, ↓BP, death
phlebitis at IV sites—most antibiotics are very irritating
Superinfections
Normal flora protect the human host by occupying space and consuming nutrients
If normal flora is suppressed by antibiotics, pathogens such as candida and c. difficile will take over!
Nephrotoxicity
acute interstitial nephritis—hematuria, (hypersensitivity rx that can occur with many antibiotics)
Antibiotics: Nursing Actions
assess for therapeutic response—(i.e.
Lowered fever, lowered WBC, lowered drainage, lowered pain)
Continue antibiotic for full length of treatment
Space doses evenly
Contact prescriber if no improvement occurs within 3 days
Stop *drug and notify physician if rash, itching or SOB occurs
Abdominal cramps or GI distress is common – try eating small meals
If diarrhea occurs, increase fluid intake and contact your physician if symptoms don’t improve in 24hr
Report signs of a superinfection to physician immediately
Use a backup method of birth control for the duration of therapy
Must monitor serum drug levels to prevent toxicities
Peak: 4-10 mcg/mL
Trough: 0.5-2 mcg/mL
