Antibiotics Flashcards
What are the two types of antibiotics?
Bacteriostatic & Bactericidal
Explain Bacteriostatic
Prevents reproduction of bacteria and fights off the bacteria already in our body.
Explain Bactericidal
kills bacteria directly.
What is the Goal of Antibiotic Therapy?
Decrease the population of the invading bacteria to a point where the human immune system can effectively deal with the invader - we still want our immune system to do its job.
How do we select the treatment for an bacterial infection?
- First we get a patient sample.
- By Identification of the causative organism.
- Based on the culture report, an antibiotic is chosen that has been known to be effective at treating the invading organism.
- In the meantime we can use a broad specter antibiotic which is an antibiotic that we know works for lot of different infections.
CULTURE MUST BE TAKEN BEFORE ADMINISTRATION OF ANTIBIOTIC! - If we take it after administering it can affect the sample.
What must be completed prior to administrating antibiotics?
Culture
What are the 4 classifications of bacteria?
Gram-positive
Gram-negative
Aerobic
Anaerobic
Explain Gram-positive bacteria.
The cell wall retains a stain or resists decolorization with alcohol.
Explain Gram-negative bacteria.
The cell wall loses a stain or is decolorized by alcohol
Explain Aerobic bacteria.
Depend on oxygen for survival.
Explain Anaerobic bacteria.
Does not depend on oxygen. An example is gangrene.
Explain the concept of bacterial resistance to antibiotics.
Bacteria adapt to their environment.
The longer an antibiotic has been in use, the greater the chance that the bacteria will develop into a resistant strain
What is penicillinase?
The bacteria has become resistance to penicillin.
What is a sensitivity report?
we use the report to determine if the antibiotics that the patient is on is going to be effective or not.
If it has an ‘R’ after its name it means that the bacteria is Resistant to this antibiotic. If it has an ‘S’ after its name it means that the bacteria is sensitive to this antibiotic and we want to keep using or switch to this antibiotic. If it has an ‘I’ after it, it means intermediate, so it means that it might work or not.
What lifespan consideration should be taken when administering antibiotics to children?
- Kids are more sensitive to adverse effects - have more GI and CNS reactions.
- Monitor hydration and nutrition esp. with GI effects.
- Super infections, especially thrush/oral candidiasis - can make eating and drinking painful.
- Many do not have proven safety and efficacy
- Some can cause harm to growing cartilage, bones, and teeth
- Double check doses
- Parent education
What lifespan consideration should be taken when administering antibiotics to adults?
- Patient education
- Only use as needed
- Take entire course
- Do not take antibiotics not prescribed to you
- Don’t save antibiotics for future use
- Pregnancy and lactation - Only if benefits outweigh risks
- Adverse effects can affect fetus and neonates
- i.e. tetracyclines can damage teeth and bones; aminoglycosides can cause hearing loss
- Drug-Drug interactions: Oral contraceptives
What lifespan consideration should be taken when administering antibiotics to older adults?
- Signs and symptoms of infections are different in the older adult - many don’t get fevers.
- Only use as needed
- Take entire course
- More susceptible to adverse effects
- Monitor hydration
- Safety precautions
- Renal and hepatic impairment
- Start low, go slow
What are the suffix(ex), drug names and potential outlier for the Aminoglycosides antibiotics?
- Gentamicin
- -mycin
- Neomycin
- Streptomycin
- Tobramycin
What is the indication for giving patients Aminoglycosides?
Serious Bacterial infections
How does Aminoglycosides work in the body?
They are Bactericidal - Go in and kill the bacteria.
What are the contraindications to giving patients Aminoglycosides?
Absolute Contraindication: Anaphylactic allergy
Relative Contraindications :
Renal (Due to adverse effect of nephrotoxicity)
Hepatic disease (can effect metabolism) ,
Hearing loss - Drugs can cause ototoxicity.
Myasthenia Gravis or Parkinsonism (can be worsened with he use of Aminoglycosides),
Pregnancy or Lactation.
What are some known adverse reactions that patients who are taking Aminoglycosides may experience?
- CNS effects due to the effect on nerves incl ototoxicity (often irreversible)
- Nephrotoxicity (usually reversible once medication is stopped)
- Bone marrow depression
Are there any known DDI’s with Aminoglycosides and if so, what are they?
- Penicillin’s & cephalosporins when used together with Aminoglycosides it can have an synergistic (increasing) effect.
- Loop diuretics due to loop diuretics also being ototoxic.
- Parenteral penicillin inactivates parenteral Aminoglycosides.
Prior to giving a patient Aminoglycosides what are some patient assessments that we should be doing?
History
* Allergy, renal or hepatic disease; preexisting
hearing loss; Myasthenia Gravis & Parkinsonism
* Pregnancy or lactation
* Physical exam
* CNS: Orientation/LOC
* Auditory testing
* Vital signs
* Labs: C&S, renal function, hepatic function, CBC- due to adverse bone marrow depression risk.