Antimicrobial Therapy Flashcards
CNS Toxicity
PCN, cephalosporins, quinolones, imipenem
Hematologic toxicity w/ prolonged use
Nafcillin, piperacillin, cefotetan, chloramphenicol, trimethoprim
Reversible nephrotoxicity
Aminoglycosides & vancomycin
Photosensitivity
Azithromycin, quinolones, tetracyclines, pyrazinamide, sulfamethoxazole, and trimethoprim
Penicillins: moa
MOA: inhibit the growth of sensitive bacteria by inactivating enzymes located in the bacterial cell membrane
PCNs pathogens covered
-Gram +, gram -, most anaerobes
PCNs ADR & Monitoring
hypersensitivity, rash, drug fever, GI effects, hepatitis, interstitial nephritis, leukopenia, thrombocytopenia, Coomb’s (+) hemolytic anemia, C.Diff, electrolyte changes, seizures
-monitor: hypersensitivity reactions, renal function, hepatic function, CBC
PCN drugs
- Broad spectrum
- Amoxicillin
- Ampicillin
- Dicloxacillin
- Nafcillin
- Oxacillin
- Penicillin G, V (more narrow)
- Piperacillin
Cephalosporins MOA
inhibit the growth of sensitive bacteria by inactivating enzymes located in the bacterial cell membrane
Cephalosporin common pathogens covered
5 generations with increasing coverage; gram (+) cocci (minus enterococcus), gram (-) coverage.
Cephalosporin ADR & Monitoring
hypersensitivity, rash, drug fever, GI effects, hepatitis, interstitial nephritis, leukopenia, thrombocytopenia, Coomb’s (+) hemolytic anemia, C.Diff, coagulopathy
- monitoring: hypersensitivity reactions & rash, renal function, hepatic function, CBC
- Of note: do not use in patients with hx of IgE mediated allergy to PCN
List of Cephalosporin Drugs 1st generation
- Good for bone infections, ear infections, skin infections, URIs and UTIs
- Cephalexin (keflex, Biocef)
- cefadroxil (Duricef)
- cephradine (Panixine)
- cefazolin (ancef)
Cephalosporin drugs: 2nd generation
- Bone & joint infections, gynecological, intra-abdominal, lower respiratory, skin and skin structures infections, UTIs
- More active against gram negative
- cefuroxime (Ceftin)
- cefprozil (Cefzil)
- cefoxitin (Mefoxin)
- cefuroxime (Zinacef)
- cefotetan (efotan)
Cephalosporin drugs: 3rd generation
- More narrow
- Bactermia/septicemia, bone & joint, CNS, gynecological, intra-abdominal, lower respiratory, skin & skin structures infections, UTIs
- ceftriaxone (Rocephin)
- cefdinir (Omnicef)
- cefixime (Suprax)
- cefpodoxime (Vantin)
Carbapenems MOA
inhibit the growth of sensitive bacteria by inactivating enzymes located in the bacterial cell membrane
Carbapenems common pathogens covered
Gram neg, anaerobes, gram +
Carbapenems ADR & Monitoring
- Hypersensitivity reaction, rash, headache, GI, seizures, drug fever, eosinophilia, thrombocytopenia, hepatitis, Clostridium difficile
- Monitoring: hypersensitivity reactions, renal function, hepatic function, CBC
- Of note: Cross sensitivity with PCN 50%, clinically relevant 1%. Seizure risk highest with imipenem-cilastatin (elderly, history of seizures, renal dysfxn)
Carbapenem drugs
- Class of beta-lactam
- Often reserved for more severe infections (last line)
- etrapenem (Invanez)
- cilastatinin/imipenem (Primaxin)
- doripenem (Doribax)
- meropenem (Merrem)
Monobactams-Aztreonam MOA
MOA: inhibit the growth of sensitive bacteria by inactivating enzymes located in the bacterial cell membrane
Monobactams-Aztreonam common pathogens covered
gram (-) – including Enterobactericeae and pseudomonas
-Monobactams used to treat: pyelonephritis, uncomplicated cystitis, lower RI, septicemia, skin infections, perotinitis, endometrosis
Monobactams - Aztreonam drugs
- Azectam
- Aztreonam
- Cayston
- Aztreonam inhalation
Monobactams - Aztreonam ADR & monitoring
rash, nausea, diarrhea, hepatitis, thrombocytopenia, Clostridium difficile
- Monitor: Renal & hepatic
- May be used in pts w/ PCN/cephalosporin allergy
Aminoglycosides MOA
moa: binding to aminoacyl site of 16S ribosomal RNA within 30S ribosomal subuit -> misreading of genetic codes, thus inhibits translocation
Aminoglycosides common pathogens covered
bactericidal against gram (-) aerobes
-also effective against staphylococci & myobacterium tuberculosis
Aminoglycosides ADR & Monitoring
- tubular necrosis & renal failure, vestibular and cochlear toxicity, neuromuscular blockade, vertigo, anemia, hypersensitivity
- Monitoring: Renal function, serum drug concentration, serum calcium, magnesium, sodium. Monitor for nausea, vomiting, nystagmus, vertigo
- ototoxicity may be irreversible
Aminoglycoside drugs
- generally broad spectum and potent
- often used in combo
- poor GI absorption so often given IV
- tobramycin (Kitabis, Nebcin)
- neomycin (Neo-Fradin)
- amikacin (Amikin)
- gentamicin (Garamycin)
Lipopeptides-Daptomycin MOA
cyclic lipopeptide – calcium-dependent polarization of gram (+) cell membranes
Lipopeptides-Daptomycin Common pathogens covered
Gram +, MRSA, VRE
Lipopeptides-Daptomycin ADR & Monitoring
Monitoring: LFTS, muscle pain/weakness, CPK baseline & weekly – some may need more frequent monitoring. Discontinu if CPK > 10 ULN or if myopathy + CPK > 1000 IU/L
- hepatotoxicity, CPK elevation, myopathy, diarrhea, eosinophilic pneumonia, Clostridium difficile
- May want to stop statin therapy during daptomycin
-Lipopeptides-Daptomycin Drugs
Daptomycin Bacillomycin surfactin mycosubtillin caspofungin -used for complicated skin and skin structure infections, bacteremia
Glycopeptides-Vancomycin MOA
MOA: inhibits bacterial cell wall synthesis
-Common pathogens covered gram +, MRSA
Glycopeptides-vanco ADR & monitoring
- ADR: Red man syndrome, phlebitis, renal dysfunction, neutropenia, leukopenia, eosinophilia, thrombocytopenia, drug fever
- Monitoring: renal function, CBC, serum drug concentration
Oxazolidinones-linezolid & tedizolid MOA
MOA: inhibit bacterial protein synthesis at 50S ribosome, suppress toxics such as Panton-Valentine leucocidin, alpha-hemolysin, and toxic shock syndrome toxin-1
Oxazolidinones – linezolid and tedizolid: Common pathogens
bacteriostatic; gram (+) organisms
Oxazolidinones – linezolid and tedizolid ADR & Monitoring
ADR: myelosuppression, peripheral neuropathy, optic neuropathy, blindness, lactic acidosis, diarrhea, nausea, serotonin syndrome, interstitial nephritis
- Monitoring: serotonin syndrome, CBC with diff. With long-term therapy – visual acuity and other visual tests
- Of note: myelosuppression associated with > 2 week therapy and is reversible
Tetracyclines: doxycycline, tetracycline, minocycline, tigecycline, eravacycline, sarecycline, omadacycline
-MOA
Mechanism of action: inside of cell wall binds reversible to 30S ribosomal subunit – ultimately inhibiting protein synthesis producing a bacteriostatic effects
Tetracyclines common pathogens covered
-gram (+) and gram (-), atypical pathogens
Tetracyclines: ADR & Monitoring
- GI upset, NVD, hepatoxicity, esophageal ulcerations, photosensitivity, azotemia, visual disturbances, vertigo, hyperpigmentation, deposition on teeth, hemolytic anemia, pseudotumor cerebri, pancreatitis, Clostridium difficile
- Monitoring: CBC with diff, LFTs, renal function
- Of note: doxycycline preferred with renal dysfunction, vestibular symptoms women > men. Do not use in pregnancy or in children
Rifamycines-rifampin, rifabutin, rifapentine MOA
thought to inhibit bacterial DNA-dependent RNA polymerase
Rifamycines-rifampin, rifabutin, rifapentine Common pathogens covered
mycobacterial infections, selective invasive staphylococcal infections
Rifamycines-rifampin, rifabutin, rifapentine: ADR & Monitoring
- Discolored urine, tears, contact lens, sweat, hepatotoxicity, GI upset, flu-like syndrome, hypersensitivity, thrombocytopenia, leukopenia, drug fever, interstitial nephritis
- Monitoring: LFTs, bilirubin, renal fxn, CBC at baseline + q2weeks if patient is also receiving hepatoxic medications or if have impairment
Macrolides-azithromycin, clarithromycin MOA
MOA: bind to 50S subunit of bacterial ribosomes – leading to inhibition of bacterial protein synthesis
Macrolides-azithromycin, clarithromycin common pathogens covered
mycobacteria, gram (-), atypical, and some gram (+)
Macrolides-azithromycin, clarithromycin: ADR & Monitoring
GI intolerance, prolonged QTc, cholestatic hepatitis, ototoxicity (reversible), TDP, rash, hypothermia, exacerbation of myasthenia gravis
Monitoring: LFTS, ECG if high risk
lincomycin class: Clindamycin MOA
-binds to 50S ribosomal subunit of bacteria; disrupts bacterial protein synthesis, post-antibiotic effect. Generally thought to be bacteriostatic, but can be bactericidal with some organisms
Bacteriostatic
-agent prevents the growth of bacteria
Bacteriocidal
-Kills bacteria
Clindamycin common pathogens covered
anaerobes, streptococcus, staphylococcus
Clindamycin ADR & Monitoring
- diarrhea, Clostridium difficile, nausea, vomiting, generalized rash, hypersensitivity
- Monitoring: renal and liver function for prolonged therapy. Monitor for diarrhea – common cause of Cdiff colitis.
Fluoroquinolones – besifloxacin, ciprofloxacin, levofloxacine, gatifloxacin, moxifloxacin, ofloxacin MOA
bactericidal – directly inhibit bacterial DNA synthesis
Fluoroquinolones – besifloxacin, ciprofloxacin, levofloxacine, gatifloxacin, moxifloxacin, ofloxacin common pathogens covered
aerobes, gram (-), respiratory pathogens, some gram (+) organisms
Fluoroquinolones – besifloxacin, ciprofloxacin, levofloxacine, gatifloxacin, moxifloxacin, ofloxacin: ADR & Monitoring
- GI intolerance, headache, malaise, insomnia, QTc prolongation, tendon rupture, peripheral neuropathy, crystalluria, seizure, interstitial nephritis, SJS, allergic pneumonitis, Clostridium difficile
- Monitoring: renal function, confusions, hallucinations, tremor
- Of note: tendon rupture more frequently seen in elderly & kidney, heart, lung transplant patients, and concurrent use of corticosteroids
Sulfonamides & Trimethoprim MOA
- SMX – competes with PABA to inhibit dihydrofolic acid (stops converstion to tetrahydrofolic acid).
- TMP binds to bacterial dihydrofolate reductase, prevents formation of tetrahydrofolic acid. This is done preferentially in bacteria vs human. In turn, this inhibits DNA synthesis.
Sulfonamides & Trimethoprim: Common pathogens covered
gram (+), gram (-). Community acquired MRSA, Pnemocystis jirovecii, nocardia
Sulfonamides & Trimethoprim: ADR & Monitoring
- GI intolerance, rash, hyperkalemia, bone marrow suppression, serum sickness, hepatitis, photosensitivity, crystalluria with azotemia, methemoglobinemia, urolithiasis, SJ, TEN, aseptic meningitis, pancreatitis, interstitial nephritis, Sweet syndrome, neurologic toxicity
- Monitoring: hypersensitivity reactions, rash, CBC, renal function, hepatic function, potassium, serum glucose
- HIV-infected patients are increased risk for ADR
Sulfonamide drugs
- Bactrim
- Cotrim
- Septra
- Erythromycin/sulfisoxazole
Metronidazole MOA
MOA: produces free radicals that are toxic to microbe through a 4-step process
Metronidazole common pathogens covered
anaerobes, protozoa
Metronidazole ADR & Monitoring
- GI intolerance, headache, metallic taste, dark urine, peripheral neuropathy, disulfiram-like reactions with alcohol, insomnia, stomatitis, aseptic meningitis, dysarthria
- Monitoring: Liver function, mental and neurologic status
- Of note: peripheral neuropathy is reversible, associated with long-term treatment
