Antimicrobial Drugs Flashcards
PCNs, Cephalosporins, Carbapenems, and others
Drug classes that inhibit cell wall synthesis:
-Weaken the cell wall
-Influx of fluid into the cell
-Cell swells and burst
-Cell lysis and death
Penicillins
Cephalosporins
Carbapenems
Vancomycin
The function of Beta-Lactam Antibiotics
Inhibit the synthesis of the bacterial peptidoglycan cell wall
Never given individually
Ex: Sulfabactam, clavulanic acid, tazobactam, avibactam
Penicillin MOA
Disrupt the synthesis of the cell wall
-Bacteria must be growing
-Inhibit transpeptidases (cell wall synthesis)
-Activates autolysis
Adverse effects of Penicillins
Uticaria (hives), pruritis (itching), angioedema (swelling under the skin)
Indications for Penicillin
Works against many different organisms
Low toxicity
4 Different types of PCNs
-Natural PCNs (PCN G & V)
-Penicillinase-Resistant PCN (nafcillin)
-Aminopenicillins (amoxicillin & ampicillin)
-Extended-spectrum PCNs (piperacillin)
Natural PCNs and indication
Penicillin G & V
-Works well on gram +/- cocci, anaerobic bacteria, spirochetes
-Least toxic
-Can be used with aminoglycosides
PCN G&V route
Route: IV/IM (PO available)
-IM commonly used for STDs
Natural PCNs AE/considerations
-1/2 life about 30 minutes (unless kidney dysfunction
-Allergy: Rash to anaphylaxis
Allergic to 1 PCN, allergic to ALL PCNs
Penicillinase Resistant PCNs
Drug and Indication
Drug: Nafcillin
Indication: Drug of choice for Penillinase Resistant PCNs
-Can be used for staph bacteria (anti-staphylococcus PCN)
Nafcillin class and route
Class: Penicillinase
Route: IV ONLY
Aminopenicillins
Drug and MOA
Ampicillin and Amoxicillin
Disrupt the synthesis of the cell wall
-Can work better against gram (-) because of the chemical structure
Ampicillin
Indication and Route
Indication: 1st broad spectrum
Route: IV or PO (if giving PO usually prefer Amoxicillin)
Ampicillin
Adverse effects and considerations
AE: Diarrhea and rash are common
Considerations:
-Renal sensitive
-Stopping using ampicillin as much because of drug resistance
-Allergy
Amoxicillin
Indication and route
Indication:
-Very common in pediatric patients (doses are sometimes higher because of strep-resistant organisms)
-Common for ear, nose, throat, genitourinary and skin infections
Route: ONLY PO
Amoxicillin
Adverse effects and considerations
AE: Diarrhea and rash (although less side effects compared to ampicillin)
Consideration: Allergy
Extended-spectrum PCN
Drug
Piperacillin
Piperacillin
Indication
Indication:
-Wider spectrum than other PCNs
-Anti-pseudomonal (especially piperacillin)
Piperacillin
Class and nursing considerations
Class: Extended-spectrum PCN
Nursing considerations:
-Affects platelet function
-Watch for patients with renal dysfunction
-always given with a beta lactamase inhibitor
How many generations of cephalosporins?
MOA of Cephalosporins
5 Generations (later generations increase spectrum/activity/and ability to penetrate CSF)
MOA: Inhibit cell wall synthesis through PCN-binding protein (inhibit transpeptidase). Leads to autolysis
Cephalosporin (general)
Indications
Same as PCNs: Gonorrhea, UTI, Peritonitis, Meningitis, Pneumonia, etc)
Low-toxicity
-Some cross-sensitivity with PCN allergy. Avoid if PCN anaphylaxis
Cephalosporin (general)
AE and considerations
AE: mild diarrhea, abdominal cramps, rash, pruritis, redness, edema
Considerations:
-Pregnancy Category B (pretty safe, used during pregnancy)
-Poor oral absorption
1st Generation Cephalosporins
Drug and indications
Drug: Cefazolin and Cephalexin
Indications:
-Works well for gram (+) bacteria
-Staph and non-enterococcal strep infections
-Cefazolin common for surgical prophylaxis
*DO NOT work in CNS infections
Cefazolin and Cephalexin
Route
Cephalexin: Either IV or PO
Cefazolin: ONLY IV
2nd Generation Cephalosporins
Drug and indications
Drug: Cefuroxime and Cefotetan
Indications: More gram (-) coverage AND gram (+) coverage
*Cefuroxime does NOT kill anaerobic bacteria but DOES work well on intestinal bacteria
*Both DO NOT work CNS or pseudomonas
Cefuroxime and Cefotetan
Route
IV and PO
3rd Generation Cephalosporins
Drug and Indications
Drug: Ceftriaxone, Ceftazidime, Cefotaxine
Indications: Most potent in fighting gram (-) bacteria BUT much less activity against gram (+)
Ceftriaxone is EXTREMELY long-acting (once per day dosing benefit)
-Able to cross the blood-brain barrier so effective in treating meningitis and other infections within the CNS
Ceftazidime works well for Pseudomonas (although becoming more resistant)
Ceftriaxone, Ceftazidime, Cefotaxine
Route and considerations
Route: IV/IM only (other drugs are PO)
Considerations: Do NOT give Ceftriaxone to patients with liver failure (works well but hard on the liver)
4th Generation Cephalosporins
Drug and Indications
Drug: Cefepime
Indications:
-Works against gram (-) and gram (+). Very broad spectrum
-Uncomplicated/complicated UTIs, skin infections, and Pseudomonas
Crosses the BBB (works well for CNS and Pseudomonas)
5th Generation Cephalosporins
Drug and Indications
Drug: Ceftaroline
Indications:
-Treats MRSA and MSSA
-Works against some VRSA/VISA
-Mostly for nasty staph infection
*Does NOT work on enterobacter, pseudomonas, ESBL, Klebsiella coverage
Ceftaroline
Route and considerations
Route: ONLY IV
Considerations: needs to be renally dosed (hard on kidneys)
-Monitor BUN/Creatinine
Carbapenems
Drug and MOA
Drug:
-Imipenem/Cilastatin
-Meropenem
MOA: Binds to PCN-binding protein which inhibits cell wall synthesis
-Very resistant to Beta-lactamase
Imipenem/Cilastatin
Indications and Route
Indications:
-BROADEST spectrum of ALL antibiotics
-Can penetrate BBB and meninges
-Used for complicated infections
-Combo of the carbapenem with the inhibitor of the enzyme that breaks down imipenem
Route: IV only (must be infused over 60 minutes
Imipenem/Cilastatin
AE and considerations
AE: drug-induced seizure activity
Considerations:
-Monitor patients for seizures, especially in the elderly, and with other medications that can induce seizure
ALL are IV and must be INFUSED OVER 60 MINUTES
Cilastin helps inhibit dehydropeptidase that breaks down imipenem too quickly. Allows imipenem to stay in the system longer and work more effectively
Doesn’t work against CRE
Meropenem
Indications and Route
Indications:
-A little less coverage than imipenem; but still gram (+) and (-) aerobes and anaerobes
Route: IV only (infused over 60 min)
Meropenem
AE and considerations
AE:
-Less seizure activity than Imipenem/cilastatin
-Rash and diarrhea most common side effects
Considerations:
-Doesn’t degrade in kidneys
-Doesn’t work against CRE
-Must be INFUSED OVER 60 MINUTES
Glycopeptide Antibiotic
Drug and MOA
Drug: Vancomycin
MOA: Destroys by binding to the bacterial cell wall, producing immediate inhibition of cell wall synthesis and death
Vancomycin
Indications and Route
Indication:
-Works on gram (+) infections (including MRSA and PCN-resistant pneumococcus)
Route: IV (some PO for C.Diff and pseudomembranous colitis)
Vancomycin
AE and considerations
AE:
Toxic side effects:
-Ototoxicity with high levels (can be reversible)
-Immune-mediated thrombocytopenia
-Nephrotoxic→ watch when using with other drugs (aminoglycosides, cyclosporin’s, IV contrast) that affect kidneys
-Watch with neuromuscular blockades (paralyzers)
Usually NOT harmful
-Red Man Syndrome: usually related to rapid infusion (flushing, rash, pruritus, tachycardia, hypotension)
-infuse slowly and over longer periods
Considerations:
Doesn’t work for CNS infections
Kidney eliminates drug: decrease doses for renal dysfunction
-Monitor kidney levels (not as much for PO)
Draw peak and trough levels (therapeutic)
-15 to 30 minutes after med is given (peak)
- 30 minutes before next dose (tough)
Aminoglycosides
Drug and MOA
Drug: Gentamycin, Amikacin, Tobramycin
MOA: Inhibit bacterial ribosomes→ unable to make proteins
-Used in combination with beta-lactamase or vancomycin. Use other medicines first
Gentamycin, Amikacin, Tobramycin
Indications and Route
Indications:
Used since 1944 for complicated infections: UTIs/pyelonephritis, gynecological infections, peritonitis, endocarditis, PNA, osteomyelitis (DM-related infections)
Potent antibiotics that work well on gram (–) bacteria
-Also work on gram + but need other anti-biotics for a synergistic effect
Route: Mostly IM but also ophthalmic and topical
*googled
Gentamicin, Amikacin, Tobramycin
AE and considerations
AE:
Severe side effect profile:
-Nephrotoxicity: 5-25%, usually reversible
-Ototoxicity: 3-14%, usually permanent
Neuromuscular blockade → can cause PROFOUND respiratory distress (myasthenia gravis)
CNS side effects: confusion, depression, disorientation, numbness, and tingling
Cochlear damage- ototoxicity, high-frequency hearing loss, high-pitched tinnitus
Considerations:
Therapeutic drug monitoring
-Peak/Trough levels
Transitioned from 3x day dosing to 1x day dosing
Lincosamides
Drug and MOA
Drug: Clindamycin
MOA: binds to ribosomes and inhibits protein synthesis
Clindamycin
Indications and Route
Indications:
-Chronic bone infections, GU tract infections, intra-abdominal infections, anaerobic pneumonia, septicemia, serious skin infections, prophylaxis for endocarditis
Often used for anaerobic bacteria
Route: PO and IV
Clindamycin
AE and considerations
AE: very toxic
-Can cause deadly pseudomembranous colitis
Considerations:
Monitor use with neuromuscular blockade medications→ respiratory distress
Therapeutic drug monitoring
-peak and though
All enterobacter bacteria are resistant to clindamycin (doesn’t work for VRE and CRE)
Macrolides
Drug and MOA
Drug: Erythromycin and Azithromycin
MOA: Inhibit protein synthesis by binding to ribosomes
-Good at entering host cells
Erythromycin
Indications and Route
Indications: used to treat MANY infections. Has hypomotility benefits for diabetic gastroparesis and increases gastric motility and emptying
Route: PO and IV (topical and ophthalmic also available)
-IV is painful, and oral absorption isn’t great
Azithromycin
Indications and Route
Indications:
-differs structurally from other macrolides → has some advantages in coverage compared to erythromycin
-Very good at tissue penetration and long duration of action
Route: PO and IV
Erythromycin and Azithromycin
AE and considerations:
AE: YUCK drugs (GI upset, especially erythromycin)
Considerations:
Erythromycin:
-Do NOT take on an empty stomach
-Lots of drug-drug interactions
Azithromycin:
-Take WITHOUT food; taking with food decreases absorption
Macrolides
Indications (general)
Indications: various infections of upper and lower respiratory infections, skin infections, soft tissue infections; STIs
-Legionnaire’s, Listeria, and mycoplasma pneumonia can all be treated with macrolides
Tetracyclines
Drug and MOA
Drug: Tetracycline, Doxycycline, Minocycline
MOA: bacteriostatic drugs that inhibit synthesis by binding to ribosomes
Tetracycline, Doxycycline, Minocycline
Indications
Indication: Broad spectrum; major resistance has developed
Infections still commonly treated with tetracyclines:
-Rickettsia (Rocky Mountain spotted fever)
-Chlamydia and trichomonas
-Lyme disease
-Cholera
-Pelvic inflammatory disease
-Mycoplasma pneumonia
-Acne
Tetracycline, Doxycycline, Minocycline
AE and considerations
Adverse effects: discoloration of the permanent teeth and tooth enamel hypoplasia in features and children, photosensitivity, and many others
Diarrhea, yeast infections
More serious: thrombocytopenia
Considerations:
Contraindications: Pregnant and nursing women, children younger than 8 (damage teeth)
Wear sunscreen
Fluoroquinolones
Drug and MOA
Drug: Ciprofloxacin and Levofloxacin
MOA: destroys bacteria by altering their DNA (interfering with the bacterial enzymes DNA gyrase and topoisomerase)
Fluoroquinolones
Indication (general)
Mostly gram (-) and some gram (+) coverage
Very potent, broad-spectrum antibiotics
Very good oral absorption
Ciprofloxacin
Indication and Route
Indication: UTIs, some STIs, upper respiratory and lower respiratory tract infections, gonorrhea, and other infections
-Also treats anthrax→ infection with Bacillus anthracis
Minimal penetration of the BBB/CSF
Works well on rapid and slow-growing organisms
Route: PO, IV, and topical
Ciprofloxacin
AE and considerations
AE: arthropathy (joint disease), often irreversible
-prolonged post-antibiotic effects→ concentrated in the neutrophils
Considerations: Avoid in patients under 18 and over 60
Levofloxacin
Indication and Route
Indication: Most widely used quinolones
-Broad spectrum of activity like cipro but advantage is once-daily dosing
Less resistance
More activity against pneumococcal and other ‘atypical’ respiratory infections
Route: PO (100% bioavailability) or IV
Levofloxacin
AE and considerations
AE: CNS disorders that predispose to seizures, and kidney failure, can cause prolongation of QT interval, photosensitivity
Considerations: Monitor kidney levels, wear sunscreen
Sulfonamides
Drug and MOA
Drug: Sulfamethoxazole and Trimethoprim
MOA: don’t actually destroy bacteria but inhibit their growth=bacteriostatic by preventing the synthesis of folic acid needed for DNA synthesis
Sulfamethoxazole and Trimethoprim
Indications and typical population
Indications: uncomplicated UTIs, respiratory infections, salmonella, shigellosis
Population: Often given to patients with HIV
Sulfamethoxazole and Trimethoprim
AE and considerations:
AE: Sulfa allergies: usually start with fever and end with skin rash
Photosensitivity
Considerations: Adverse reactions are more common in patients with HIV
Antiprotozoal and Antibacterial
Drug and MOA
Drug: Metronidazole
MOA: inhibit DNA synthesis
(destroys bacteria by altering their DNA- interfere with the bacterial enzymes DNA gyrase and topoisomerase)
Metronidazole
AE and considerations
AE: N/V, xerostomia (dry mouth), vaginal candidiasis
Considerations:
DO NOT TAKE WITH ALCOHOL
-Cannot have had alcohol 24 hours before and 36 hours after. Can create toxic metabolic in the system
Metronidazole
Indications
Indications: Anaerobic activity only
-Crohn’s disease
-Antibiotic-associated diarrhea or C-Diff
-Antiprotozoal and antibacterial
