N333 - Exam #2 ANTIBIOTICS Part I and II

What are the 3 big “buckets” of antibiotics affecting the cell wall?

Beta-Lactams, Glycopeptides, Fosfomycin

The bacterial cell wall is composed primarily of ____ and synthesized by ____ ____ ____. Antibiotics disrupt this leading to bacterial death 

Peptidoglycan and Pencillin-Binding Proteins (PBPs)

__ ___ antibiotics contain a beta-lactam ring and inhibit PBPs causing bacterial cell lysis. They are used primarily for streptococcal infections with clinical themes including allergy assessment, renal monitoring, C. Difficile risk

Beta-Lactam

This antibiotic covers primarily gram-positive (streptococcus), anaerobes (oral flora), some gram negative meaning it has a NARROW spectrum.

Natural Penicillins 

What are the prototype drugs for natural penicillins?

Penicillin G (IV/IM) and Penicillin V (PO) 

For someone with syphillis, which natural penicillin would you use?

Penicillin G (drug of choice)

What are the ADRs for Penicillin G (Natural Penicillins Prototype)

Urticaria (hives), neurotoxicity at high doses (seizures), hyperkalemia

This antibiotic has extended gram-negative coverage (h. influenzae and e coli) and is a broader spectrum than natural penicillins 

Aminopenicillins

What are the prototype drugs for aminopenicillins?

Ampicillin and Amoxicillin (preferred for endocarditis prophylaxis)

This antibiotic is resistant to beta-lactamase and mainly used to treat against MSSA (osteomyelitis/endocarditis/bacteremia)

Penicillinase-Resistant

What are the prototype drugs for penicillinase-resistant antibiotics?

Nafcillin, Oxacillin, Dicloxacillin

What are the ADRs for Nafcillin (Pencillinase-Resistant Prototype)

Rash, Neutropenia, Hepatotoxicity (liver function tests AST/ALT), C. Difficile Associated Diarrhea 

What route should you administer penicillinase-resistant antibiotics like nafcillin?

IV/IM

This antibiotic has broader gram-negative coverage including Pseudomonas (often combined with β-lactamase inhibitors)

Extended-spectrum

What are the prototype drugs for Extended-spectrum antibiotics?

Piperacillin, Ticarcillin

Why would you use extended-spectrum antibiotics?

Severe or polymicrobial infections (HAP, Sepsis, Comp UTI)

What are the ADRs of Piperacillin (Extended-Spectrum Prototype)

Hypokalemia (monitor electrolytes), C. Difficile associated diarrhea (ROUTE = IV only)

These antibiotics have a β-lactam ring + six-member dihydrothiazine ring with generational progression (as generation INCREASES, gram negative coverage and β-lactamase resistance INCREASES)

Cephalosporins

1st Gen Cephalosporins = CEFAZOLIN

Primarily gram positive

2nd Gen Cephalosporins = CEFUROXIME

Increased gram-negative coverage

3rd Gen Cephalosporins = CEFTRIAXONE

Broad gram-negative and increased CNS penetration

4th Gen Cephalosporins = CEFEPIME

Strong gram-positive & gram-negative (incl. Pseudomonas)

5th Gen Cephalosporins = CEFAROLINE

Active against MRSA (R = really resistant need stronger antibiotics)

What is the prototype drug for cephalosporins? *Monitor renal function (creatine and BUN) 

Cephalexin (ADRs = Rash/GI Upset/C. Difficile Infection)

These antibiotics are a VERY BROAD spectrum β-lactams (β-lactamase resistant) which means it covers gram positive, negative, anaerobes, and many multidrug resistant organisms (MDROs)

Carbapenems

What is the prototype drug for Carbapenems?

Meropenem

What are carbapenems used for and what ADRs are associated with meropenem

Severe or high-risk infections (big gun antibiotic). N/D/R, seizures (renal impairment), C. difficile infection

These antibitoics are very NARROW spectrum and are used for serious aerobic gram negative infections (includes pseudomonas)

Monobactams (minimal disruption of gram+ flora)

What is the prototypes for monobactams and what is a common ADR?

Aztreonam and elevated liver enzymes

____ antibiotics bind to D-Ala-D-Ala inhibiting cell wall elongation and cross linking 

Glycopeptides

What is the prototype drug for glycopeptide antibiotics that is used for serious gram positive infections by IV (MRSA, enterococcus/streptococcus and clostridioides difficile for oral therapy)

Vancomycin

What is the first line treatment for clostridioides difficile

Oral vancomycin

What ADRs are associated with vancomycin?

Nephrotoxicity, ototoxicity (hearing loss/ringing), and infusion related "Red man syndrome" (flushing & hypotension - importance of infusing IV over at least 60 minutes) 

___ antibiotics inhibit bacterial cell wall synthesis by blocking enolpyruvyl transferase so cells cannot bind to uroepithelial cells and are used for acute uncomplicated cystitis in women and resistant strains, including ESBL-producing organisms & VRE

Fosfomycin

These one time use antibiotics work best when you dissolve the powder in water and take immediately on an empty stomach

Fosfomycin

___ antibiotics are used for BROAD spectrum infections (gram positive, gram negative, atypical pathogens) mainly lung infections, chlamydial infections, GI infections, Lyme Disease

Tetracycline

What are the prototype drugs for tetracyclines (protein synthesis inhibitor)?

Tetracycline and doxycycline (longer half life and twice daily dosing) 

What ADRs are associated with tetracyclines?

GI upset, photosensitivity, C. difficile-associated diarrhea, hepatotoxicity, Stevens-Johnson syndrome, Pseudomembranous colitis

___ antibiotics absorption is significantly reduced by polyvalent cations (calcium/iron/magnesium). You must also NOT GIVE to pregnant women or children younger than 8 years old 

Tetracyclines

What are the prototype drugs for macrolides?

Erythromycin and Azithromycin

___ have a moderate spectrum (gram + and select gram -) cover atypical infections  (Mycoplasma, Chlamydia, Legionella) and are used for lung infections, chlamydial infections, Group A strep 

Macrolides (Erythromycin and Azithromycin)

___ is the preferred macrolide antibiotic due to longer half-life requiring less frequent dosing, improved GI tolerability (GI upset with erythromycin so you should administer with food)

Azithromycin

What are the prototype drugs for aminoglycosides?

Gentamicin

___ antibiotics have a NARROW spectrum (aerobic gram-negative) and are used for serious systemic infections, HAP, septicemia, endocarditis and should be administered via IV

Aminoglycosides (Gentamicin)

What ADRs are associated with Gentamicin (Aminoglycoside Prototype)

Nephrotoxicity and Ototoxicity (high toxicity risk)

___ has a Black Box Warning due to risk of irreversible hearing loss or kidney damage

Gentamicin (Aminoglycosides)

What are the prototype drugs for lincosamides?

Clindamycin (administer with a full glass of water to reduce esophageal irritation)

___ antibiotics are used for gram positive (streptococcus, MSSA) infections with strong anaerobic coverage 

Lincosamides (Clindamycin)

What is the ADR associated with Clindamycin (Lincosamides)

Diarrhea with HIGHEST association for risk for C. difficile/Pseudomembranous colitis and Stevens Johnson Syndrome 

What are the prototype drugs for Oxazaolidnones?

Linezolid

___ antibiotics have a narrow spectrum (gram positive only including MRSA and VRE) and are used for serious resistant gram-positive infections (HAP)

Oxazaolidnones (Linezolid)

What ADRs are associated with Linezolid (Oxazaolidnones)

Myelosuppression (↓ platelets) and peripheral/optic neuropathy 

___ have a WEAK MAOI which increases the risk for serotonin syndrome with SSRIs/SNRIs and forces one to avoid high tyramine-containing foods (aged cheese)

Linezolid (Oxazaolidnones)

___ was one of the first antibiotics discovered to inhibit bacterial protein synthesis and has a BROAD spectrum used for serious infections like typhoid fever + meningitis

Chloramphenicol

What ADRs are associated with Chloramphenicol

Bone marrow suppression, aplastic anemia, gray baby syndrome (in neonates due to immature liver metabolism)

____ antibiotics are nucleic acid synthesis inhibitors that have a broad spectrum and are used for UTIs, CAP, pneumonia

Fluoroquinolones

What are the prototype drugs for Fluoroquinolone’s?

Ciprofloxacin and Levofloxacin

What are the ADRs associated with fluoroquinolones?

CNS effects, QT prolongation, Tendinitis/tendon rupture, peripheral neuropathy, photosensitivity

____ have a Black Box Warning for increased risk of tendon rupture and should be avoided with antacids/iron/calcium (↓ absorption); avoid in pregnancy & children

Fluoroquinolones (Ciprofloxacin and Levofloxacin)

What is the prototype drug for Rifamycins?

Rifampin

___ is a nucleic acid synthesis inhibitor that has a narrow spectrum (primarily mycobacteria (TB and MAC) and used for Active TB

Rifamycin (Rifampin)

____ is a strong CYP450 inducer → major drug interactions

Rifampin (Rifamycin)

What are the ADRs associated with Rifampin (Rifamycin)

Hepatotoxicity; Orange/red body fluids; GI upset 

___ are nucleic acid synthesis inhibitors used for anaerobic bacteria and protozoa 

Nitroimidazoles

What is the prototype drug for Nitroimidazoles?

Metronidazole

What are the ADRs associated with Metronidazole (Nitroimidazoles)

Metallic taste, peripheral neuropathy, seizures (rare), disulfiram-like reaction with alcohol - MUST avoid alcohol

___ are nucleic acid synthesis inhibitors that are used for urinary tract infections 

Nitrofurans

What are the ADRs associated with Nitrofurans

Pulmonary toxicity, hepatotoxicity, neuropathy, hemolytic anemia in G6PD deficiency and a harmless dark yellow/brown urine discoloration

Contraindications of severe renal impairment (CrCl <30 mL/min), late pregnancy (38–42 weeks, risk of neonatal hemolytic anemia) are associated with what antibiotic

Nitrofuran

___ is used for MDROs and severe resistant hospital acquired infections leading to monitoring for nephro and neuro toxicities and is a LAST LINE therapy for resistant gram negative infections

Polymyxin (Prototype Polymyxin B)

____ is used for gram positive organisms (MRSA/VRE) leading to monitoring of myopathy which can increase CPK *potent agent for resistant gram positive infections

Daptomycin

___ is a sequential blockade of bacterial folate synthesis with a broad spectrum used for uncomplicated UTIs, PJP, skin/tissue infections 

Sulfamethoxazole (Sulfonamide) Trimethoprim - Combo = SMX/TMP (SYNERGISTIC EFFECT bactericidal together but bacteriostatic alone)

What ADRs are associated with SMX/TMP 

Hyperkalemia, bone marrow suppression, SJS/TENS, Hemolysis in G6PD deficiency 

___ has a very narrow spectrum is used for Clostridioides difficile only and has minimal systemic exposure to preserve normal gut flora better

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