Penicillins and Cephalosporins Flashcards
Bacteria that are rod-shaped are called
bacillus
Bacteria that are spherical are called
cocci
Cocci bacteria that form strings are called
streptococci
Cocci bacteria that form clusters are called
staphylococci
Gram + bacteria are characterized by
strong cell walls but overall cell weakness
Gram - bacteria are characterized by
weak cell walls but overall cell strength
The smallest pathogen is the ________.
It is also the _______ to fight.
virus
toughest, most difficult
____ infections are mostly found in the skin or subcutaneous tissues.
fungal
What is the definition of a bacteriostatic drug?
A drug that inhibits the growth of bacteria
What is the definition of a bactericidal drug?
A drug that kills the bacteria
What are the five mechanisms of antibacterial action that inhibit or destroy the target bacteria?
- inhibition of the cell-wall synthesis
- alteration of membrane permeability
- inhibition of the synthesis of bacterial RNA and DNA
- Interference with the metabolism within the cell.
- Inhibition of protein synthesis
What body defences have an impact on the drug/bodies ability to fight off the infection?
Age Nutrition Immunoglobins Circulation (WBCs) Organ function
Define a natural or inherent resistance
resistance w/o previous exposure
Define an acquired resistance
resistance stemming from previous exposure to the antibacterial
Define nosocomial infections
infections obtained by exposure at the hospital
Define cross-resistance
Resistance to an antibacterial that steps from exposure to different antibacterial which has a similar action in the body.
A potentiative effect is
where one antibiotic increases the effectiveness of the second antibiotic
The main adverse reactions to antibiotics are
allergic reaction (hypersensitivity)
severe allergy; anaphylactic shock
superinfection
organ toxicity
Narrow-spectrum drugs are effective against
one type of organism
Broad-spectrum drugs are effective against
both gram+ and gram- organisms
The most common sites of organ toxicity are
ear
liver
kidney
Superinfections are
Are secondary infections where normal flora are killed and which normally occur when the patient is treated for more than one week.
Sites that are often affected by superinfections are
Sites often affected are the mouth, skin, respiratory tract, vagina, and intestines.
Culture and sensitivities are done when an infection is suspected. What is each of these components?
Culture - identifies the type of bacteria
Sensitivity - identifies the antibacterial that is most effective against the bacteria strain.
What should be done before initiating antibacterial therapy?
Culture and sensitivity (C&S)
The structure of penicillin is…
beta-lactam
The structure of penicillin causes what to happen to the bacteria?
It inhibits the synthesis of the bacterial wall
Name the four types of penicillin
General
Broad-Spectrum
Penicillinase-Resistant (Antistaphylococcal)
Extended-Spectrum (antipseudomonal)
What are the general penicillins and their route ?
Penicillin G - given IV, IM
Penicillin V - given PO, (effective against anthrax)
Which penicillins fall in the broad-spectrum category?
amoxicillin (PO) - most prescribed penicillin
ampicillin (PO/IM/IV)
Broad-spectrum penicillins (aminopenicillins) are effective against
gram+ and gram- E-coli Haemophilus influenzae shigella dysenteriae proteus mirabilis salmonella
Penicillinase-Resistant (antistaphylococcal) penicillins include
dicloxacillin (PO)
nafcillin (IM/IV)
oxacillin (IM/IV)
Penicillinase-resistant penicillins (antistaphylococcal) are effective against
most gram+ bacteria
Staphylococcus aureus
less effective than penicillin G against gram+
Extended-spectrum penicillins (antipseudomonal) include
carbenicillin idanyl (PO)
piperacillin-tazobactam (IV)
ticarcillin-clavulanate (IV)
Extended-spectrum penicillins (antipseudomonal) are effective against
gram- bacteria pseudomonas aeruginosa proteus serratia klebsiella pneumoniae enterobacter Acinetobacter
Beta-Lactamase Inhibitors are
combination drugs of a broad-spectrum antibiotic combined with beta-lactamase enzyme resulting in an antibiotic acid with increased effectiveness and extended life.
The beta-lactamase inhibitors are
amoxicillin-clavulanic acid (PO)
ampicillin-sulbactam (IV)
piperacillin-tazobactam (IV)
ticarcillin-clavulanic acid (IV)
Because beta-lactam antibiotics are excreted via the kidneys, older adult patients should have what labs monitored.
BUN
serum creatinine
clinical manifestations of severe allergic responses to antibiotics include
laryngeal edema
severe bronchoconstriction
stridor
hypotension
Assessment for penicillins
Assess for allergy to penicillins or cephalosporins
Evaluate labs, esp. liver enzymes
Record urine output; must be >600ml/d
Interventions for penicillins
C and S Monitor for superinfection (stomatitis, genital discharge, anal or genital itching) Monitor for allergic response Have epi ready Assess for bleeding DO NOT MIX PNC WITH AMINOGLYCOSIDES!
Patient teaching for penicillins
Take ALL of the prescribed meds Wear med alert tags for allergies Report side effects/ adverse rxn Increase fluid intake Chew or crush chewable tabs use secondary contraceptives may take with a snack (otherwise 1h before or 2hr after meals)
Cephalosporins act against the bacteria by
inhibiting the bacterial enzyme necessary for cell wall synthesis causing water to infiltrate the cell and cause cell lysis.
The four groups of cephalosporins are called
generations
each successive generation is less affected by ____ and more effective against ____.
beta-lactamase
gram-negative organisms
cephalosporins treat what type of infections
respiratory, urinary, skin, bone, joint, and genital infections
First-generation cephalosporins include
They are effective against
cephalexin
cefazolin
effective against e. Coli, klebsiella
Second-generation cephalosporins include
cefaclor
cefoxitin
effective against gram- and gram+
Neisseria gonorrhoea, Haemophilus influenzae, Neisseria meningitidae
Third-generation cephalosporins include
cefoperazone
ceftriaxone
effective against gram+ and gram-
pseudomonas aeruginosa
Fourth-generation cephalosporins include
cefepime
effective against gram+ and gram-
streptococci
staphylococci
side effects/adverse rxns of cephalosporins are
N/V/D weakness pruritus/rash gi distress with high doses: platelet aggregation, seizures, nephrotoxicity anorexia
cephalosporins interact with
alcohol
uricosurics (for gout)
alcohol with cephalosporins cause
flushing dizziness HA N/V muscular cramps
Uricosurics combined with cephalosporins cause
decreased cephalosporin secretion and possible toxicity
Interventions for cephalosporins include
assessment for allergy C and S assess kidney and liver fx administer IV over 30 minutes bid-qid monitor for superinfection monitor for severe diarrhea
Teaching for cephalosporins include
Take ALL of the prescribed medication
wear an alert bracelet for allergies
ingest buttermilk, yogurt, or acidophilus supplement
monitor for superinfection
