Antimicrobials Part 2 (Pharmacology Exam 2)
What is the MOA of Penicillin G (benzylpenicillin)**?
- target PCN-binding proteins to weaken bacterial cell wall through inhibition of transpeptidases and disinhibition of autolysins
How long does it take for an accelerated penicillin allergy to appear?
1 - 72 hours
How long does it take for an immediate penicillin allergy to appear?
2 - 30 minutes
What is Azithromycin used for?
: most gram + and some gram - coverage
What is the medication class of Gentamicin?
Aminoglycoside
5th Ceftaroline are used for?
Broad spectrum, mostly SSTI (skin to soft tissue- pts who have lots of burns) and PNA
How long does it take for a delayed penicillin allergy to appear?
Days - Weeks
What are the Drugs That Inhibit Bacterial Protein Synthesis & DNA Replication?
Doxycycline Azithromycin Clindamycin (Cleocin) Linezolid (Zyvox) Gentamicin Sulfamethoxazole/Trimethoprim (Bactrim) Nitrofurantoin (Macrobid) Ciprofloxacin (Cipro) Metronidazole (Flagyl) Daptomycin (Cubicin)
What is a nursing consideration of Clindamycin (Cleocin) with concurrent use with NMBA?
Excessive neuromuscular blockade and respiratory paralysis
What should be watched for when giving Clindamycin (Cleocin)?
I/O and hypotension with IV infusions
What medication class is Clindamycin (Cleocin) part of?
Lincosamide
What should be monitored for when giving Linezolid (Zyvox)?
Monitor CBC and I/O Monitor for drug interactions with MAO (hypertensive crisis) and SSRI (serotonin syndrome)
What are Drugs That Weaken the Bacterial Cell Wall?
Penicillin G (benzylpenicillin)** Piperacillin/tazobactam (Zosyn) Cephalosporins Imipenem/cilastatin (Primaxin) Vancomycin (Vancocin)
Ultimately the best way to fight infections is?
Prevention measures such as hand washing proper PPE etc. and correct use of medications- this prevents resistance
What occurs in an anaphylactic reaction?
Rapid Onset Dyspnea- tight throat, bronchospasm, Laryngeal Edema Feelings of apprehension Tingling ans swelling in Mouth, Face, Throat and tongue Decreased BP Tachycardia LOC
What are resistant to this enzyme?
Some PCN (i.e. nafcillin)
What kind of infections is Linezolid (Zyvox) used for?
VRE and MRSA infections S. aureus & s. pneumo HCAP S. pneumo CAP Staph and strep complicated & uncomplicated skin and skin structure infections
Other PCN are combined with a beta-lactamase inhibitor, such as?
amoxicillin with clavulanate potassium (Augmentin) and ampicillin with sulbactam (Unasyn).
How does Linezolid (Zyvox) work?
bacteriostatic abx that binds to 23S portion of 50S ribosomal subunit to block formation of initiation complex
How does Azithromycin work?
bacteriostatic abx that binds to 50S ribosomal subunit to block addition of new amino acids to growing peptide chain
like penicillins, cephalosporins work how?
bind to penicillin-binding proteins to disrupt cell wall synthesis and activate autolysins.
How does Imipenem/cilastatin (Primaxin) work?
binds specifically to PBP 1 & 2 to weaken cell wall and can resist beta-lactamases
Beta lactamase has what function?
breaks a bond in the B-lactam ring of penicillin to disable the molecule
4th and 5th generation agents have?
broad spectrum coverage, including against MDRO.
Due to structural similarities, patients with a PCN allergy may have an allergy to what?
cephalosporin, If allergy is severe, neither medication classes should be used.
Imipenem/cilastatin (Primaxin) is Co-administered with what?
cilastatin to prevent rapid imipenem breakdown in the kidneys
Pseudomonas are?
common health care associated infections and are difficult to treat due to drug resistance
What should be avoided when giving Vancomycin (Vancocin)?
concurrent use with other nephrotoxic medications
Cephalosporin (closely related to penicillins) Generations- As a general rule, 1st generation agents will have?
coverage limited to gram + organisms
2nd Cefaclor is used for?
gram + and some gram - infections
What is Gentamicin used for?
gram + cocci and aerobic gram - bacilli
1st Cefazolin are used for?
gram + infections and surgical prophylaxis
Azithromycin can increase what?
half lives of several medications, notably theophylline and warfarin
The ability to selectively target bacterial structures only limits direct harm to?
host human cells- this is why there aren't many adverse effects with penicillins
Azithromycin should be avoided in who?
in patients with pre-existing QT prolongation; monitor on telemetry
When is Vancomycin (Vancocin)?
include gram + coverage only for bone, joint, and bloodstream infections, particularly MRSA and clostridium difficile
later generation cephalosporins have?
increasing activity against gram - bacteria and anaerobes, increasing resistance to destruction by beta-lactamases, and increasing ability to reach the cerebrospinal fluid.
When giving Clindamycin (Cleocin) what should the nurse Monitor and educate patients on?
monitoring stool and fluid status
Beta-lactamases that specifically inhibit penicillin molecules are called?
penicillinases.
Azithromycin is first line treatment for?
pertussis, diphtheria, chlamydia as well as commonly used for respiratory, GI, GU and SSTI
Bacteria with this effect can?
resist the effects of penicillin and other beta-lactam antibiotics
Doxycycline is a Specifically first-line treatment for what?
rickettsial diseases, Chlamydial diseases, brucellosis, cholera, Mycoplasma pneumonia, Lyme disease, anthrax, and gastric h. pylori
Clindamycin (Cleocin) is first line treatment for?
severe group A strep and gangrene
3rd Cefdinir are used for?
some gram + and many gram - infections
Treatment for PCN anaphylaxis will consist of?
stopping the medication, administration of epinephrine, & respiratory support.
What is the name of the medication class of Doxycycline?
tetracycline; all generics have "-cycline" suffix
What are adverse effects of Cephalosporins?
•Allergic reactions- because it's very similar to penicillin there can be cross allergies •Disulfiram-like reactions with alcohol- (feels like a bad hang over)
What should be assessed and monitored for when giving Penicillin G (benzylpenicillin)**?
•Assess for history of allergic reaction s/s; if allergic to PCN, possible allergy also to cephalosporins •Monitor CBC, V/S and infection s/s
4th Cefepime are used for?
•Broad spectrum, mostly used in UTI, SSTI, and PNA
What is possible when giving Penicillin G (benzylpenicillin)**?
•C-diff infection possible, consider co-administration with lactobacillus
What are nursing considerations of Cephalosporins?
•Due to similarity of action with PCN, nursing considerations will be the same with cephalosporins
What are the adverse effects of Penicillin G (benzylpenicillin)**?
•Generally well tolerated- (it shouldn't effect our cells because we don't have cell walls) •Allergic reactions and possible cross allergy with cephalosporins
What is Penicillin G (benzylpenicillin)** used for?
•Most used for infections caused by most gram + bacteria (i.e. strep, enterococcus, and staph)
1st Cephalexin are used for?
•gram + infections
3rd Ceftriaxone are used for?
•some gram + and many gram - infection; also can cross BBB for treatment of meningitis
What are the adverse effects of Sulfonamide?
■Hypersensitivity reactions, including SJS/TENS Blood dyscrasias
What are the adverse effects of Trimethoprim?
■Megaloblastic anemia ■Hyperkalemia ■Fetal damage
Azithromycin should be administered how?
○Administer PO on empty stomach to maximize absorption, but can give with food if upset stomach persists
What is another Nursing consideration for Vancomycin (Vancocin)?
○Appropriate hygiene and cleaning with active CDI patients
What should be assessed for when giving Gentamicin?
○Assess serum peak and trough, UOP, & CMP ○Assess hearing and balance
How does Gentamicin work?
○Bactericidal abx that binds to 30S ribosomal subunit to inhibition protein synthesis, premature termination of protein synthesis, and production of abnormal proteins
When giving Clindamycin (Cleocin) > 5 loose stools per day concerning for what?
○CDAD
What infections is Sulfamethoxazole/Trimethoprim (Bactrim) used for?
○Commonly used for UTI, otitis media, bronchitis, shigellosis, and P. jirovecipneumonia
What infections is Clindamycin (Cleocin) used for?
○Current use are for certain anaerobic infections outside CNS; can be used for bone, GU, intraabdominal, PNA, septicemia, and SSTI caused by susceptible bacteria
What are the nursing considerations of Doxycycline?
○Decreased absorption if given with metal ions, including Ca, Fe, and Mg ○Interactions with oral contraceptives and anticoagulants
What infections is Gentamicin used for?
○Ex include e. coli, Klebsiella, & pseudomonas Primarily used for serious infections
What are the adverse effects of Doxycycline?
○GI most common ○Bone growth suppression & teeth discoloration in pediatric patients ○Alterations in normal flora ○Photosensitivity
What are the adverse effects of Azithromycin?
○GI most common ○QT prolongation ○Hepatotoxicity and ototoxicity ○Numerous medication interactions
What are the adverse effects of Imipenem/cilastatin (Primaxin)?
○Generally well tolerated ○GI effects most common ○Seizures ○Superinfections
What should Linezolid (Zyvox) be given with?
○Give with food to limit GI upset
What are the adverse effects of Linezolid (Zyvox)?
○HA, N/V/D ○Myelosuppression ○Neuropathy
What should be increased when giving Gentamicin?
○Increase fluid intake unless contraindicated
What are the adverse effects of Piperacillin/tazobactam (Zosyn)?
○Low toxicity ○Allergic reactions
What should be monitored when giving Vancomycin (Vancocin)?
○Monitor trough levels and CMP for renal function
What are the adverse effects of Gentamicin?
○Nephrotoxicity ○Ototoxicity
What are the adverse effects of Vancomycin (Vancocin)?
○Nephrotoxicity ○Ototoxicity ○Red man syndrome ○VRE
Azithromycin is often the 1st alternative for?
○PCN sensitive bacterial infections if allergy is present
What are the nursing considerations of Piperacillin/tazobactam (Zosyn)?
○Same as penicillin G, plus: ○Parenteral route only, monitor IV infusion site and compatibility with other IV medications
What precautions may be needed for Imipenem/cilastatin (Primaxin)?
○Seizure precautions if needed
What are the adverse effects of Clindamycin (Cleocin)?
○Severe to fatal c. diff colitis ○Non-c. diff diarrhea
Vancomycin (Vancocin) is usually administered how?
○Usually administered IV; PO administration for CDI
When will Imipenem/cilastatin (Primaxin) be reverse used?
○in patients with infections not covered by other antibiotics
Bactericidal activity effects persist despite what?
○serum levels below minimal concentration (postantibiotic effect)
What can Imipenem/cilastatin (Primaxin) be used for?
●- Very broad spectrum with activity against most pathogens, including MDRO, for bone, joint, SSTI, UTI, intraabdominal, and pelvic infections
How does Clindamycin (Cleocin) work?
●- similar to macrolides; bacteriostatic abx that binds to 50S ribosomal subunit to block addition of new amino acids to growing peptide chain
What is Doxycycline used for?
●: broad spectrum coverage against many gram + & - organisms
What is Sulfamethoxazole/Trimethoprim (Bactrim) used for?
●Broad spectrum against gram + and gram -
What is Piperacillin/tazobactam (Zosyn) used for?
●Extended spectrum (PCN susceptible organisms plus gram - and anaerobic coverage, including pseudomonas, enterobacter, Klebsiella)
How does a penicillin resistance form?
●Genes that code for beta-lactamases can be transferred from one bacterium to another to promote spread of PCN resistance.
What class is Azithromycin a part of?
●Macrolide class abx; all generics have "-mycin" suffix, but note that some non-macrolides also have "mycin"
What medication class is Linezolid (Zyvox) part of?
●Oxazolidinone class abx
What is the MOA of Piperacillin/tazobactam (Zosyn)- (more so in the hospital setting)?
●PCN actions plus inhibition of bacterial beta-lactamase with tazobactam- (this helps prevent the buildup of resistance)
What medication class is Sulfamethoxazole/Trimethoprim (Bactrim) under?
●Sulfonamide class abx and folate synthesis inhibitor
How does Sulfamethoxazole/Trimethoprim (Bactrim) work?
●Sulfonamides and trimethoprim are bacteriostatic medications that inhibit tetrahydrofolate synthesis that is needed to make DNA, RNA, & proteins
What is Imipenem/cilastatin (Primaxin)?
●Type of carbapenem antibiotic; all generics have "-penem" suffix
How does Doxycycline work?
●bacteriostatic abx that binds to 30S ribosomal subunit to inhibit binding of transfer RNA to mRNA to inhibit protein synthesis
What is Clindamycin (Cleocin) used for?
●gram + and gram - anaerobes and most gram + aerobes
How does Vancomycin (Vancocin) work?
●inhibits cell wall synthesis by binding to molecules that serve as precursors for cell wall biosynthesis
Bacteria can also produce PBP that have what?
●low affinity for PCN.
What is Linezolid (Zyvox) used for?
●very broad spectrum coverage, including MDRO
