ID drugs Flashcards
1
Q
Vancomycin MOA and coverage
A
- Glycopeptide that inhibits bacterial cell wall synthesis by binding to d-alanyl-d-alanine cell wall precursor and blocking
- Vanc only covers gram positive bacteria, including staph (MRSA), streptococci, enterococci (not VRE) and C. DIff
2
Q
When should you consider an alternative drug fro MRSA?
A
If the MIC is >=2mcg/mL
3
Q
Vanc dosing including CrCl dose adjustments
A
- IV 15-20 mg/kg q8-12 hours
- Dose is based on actual body weight
- CrCl 20-49 q24h dosing
- C.Diff
- 125-500 QID for 10 days (upper end used for severe complicated disease)
- No dose adjustment for renal impairment
4
Q
Vanco warnings, SEs, and monitoring
A
- Ototoxicity and nephrotoxicity
- PO used only for C.Diff colitis and enterocolitis not absorbed systemically
- Infusion reaction and red mans syndrome minimum rate of infusion is 1 gram/ hour
- Monitoring: renal function, trough serum concentrations at steady state generally 30 minutes before the 4th or 5th dose
- Goal trough 15-20 mcg.mL: pneumonia, endocarditis, osteomyelitis, meningitis, bacteremia
- Goal trough other infections: 10-15 mcg/mL
5
Q
Lipoglycopeptides what is the suffix and what is the MOA
A
- vancin
- Inhibit bacterial cell wall synthesis by 1) binding to D-alanyl-D-alanine portion of the cell wall, blocking polymerization and cross-linking of peptidoglycan and 2) disrupting bacterial membrane potential and changing cell permeability
- Concentration dependent
- Similar coverage as vanc but only IV and no C. DIff
6
Q
televancin: what is it approved for?
Safety and Warnings
A
- Vibativ
- Approved for complicated skin and soft tissue infections (SSTI) and hospital acquired and ventilator associated pneomonia
- Fetal risk: obtain pregnancy test prior to starting therapy, nephrotoxicity increase in mortality with pre-exisiting moderate to severe renal impairment (CrCl<=50 mL/min) when compared to vanc
- COntrainidicated: with concurrent use of IV unfractionated heparin (UFH)
- Warnings: falsely elevated coagulation tests (aPTT, PT, INR), but does not increase bleeding risk, red man syndrome: give over 30 minutes, QT prolongation
7
Q
Oritavancin contraindications and approved treatment
Dalbavancin:
A
- Orbactiv
- Approved for SSTIs
- Use of IV UFH for 120 hours (5 days) after orivancin administration due to false elevation in aPTT
- Can cause falsely elevated PT/INR for up to 12 hours and aPTT for up to 120 hours
- Orivancin: use a different antibiotic if osteomyelitis is confirmed or suspected
- Dalbavancin (Dalvance): SSTIs: Infusion reaction with rapid infusion, Increased ALT > 3 x the ULN
- Infusion site reaction for both red man, N/V/D, rash, HA
- Extremely long half life allows single dose regimen for both
8
Q
Vancomycin glycopeptide, drug interactions
A
- Risk of nephrotoxicity is increased when other nephro drugs are use (AMGs, ampho B, cisplatin, polymyxins, cyclosporine, tacrolimus, loop diuretics, NSAIDs, radiocontrast dye.
- Vanc can also increase the risk of ototoxicity when used with other ototoxic drugs (AMGs, cisplatin, loop diuretics)
9
Q
Telavancin and Oritavancin drug interactions
A
- Tele: vibativ
- Oritacancin: Orbactiv
- Avoid televancin in patients with congenital long QT syndrom, known QT prolongation or uncompensated heart failure. Caution with other meds known to cause QT prolong
- Orivancin is a weak inhibitor of 2C9 and 2C19, and a weak inducer of 3A4 and 2D6 use caution in warfarin and other drugs
10
Q
Daptomycin MOA, and coverage
Cubicin
A
- Binds to cell membrane components, causing rapid depolarization; this inhibits intracellular replication process including protein synthesis and causes cell death.
- Concentration dependent activity
- G+, Including staph (MRSA), enterococcus (bothe species of VRE) (E. Faecium and facalis)
11
Q
When shouldnt daptomycin be used?
What is it approved for?
A
For pneumonia inactivated in the lungs by surfactant
- complicated skin and soft tissue infections, S. Aureus (MRSA), bloodstream infections, including right sided endocarditis.
- Dose adjustment at 30 CrCl
12
Q
Dapto warnings, SEs, Monitoring, and Notes
A
- Eosinophilic pneumonia: generally developes 2-4 weeks after treatment
- Myopathy and rhabdo: DC in pts with S/Sx and CPK >1000 units/L (5xULN), or in asymptomatic patients with CPK>= 2000 (10xULN)
- Can falsely elevate INR/PT but does not increase bleed
- SEs: Increased CPK,
- Monitor: CPK weekly
- Cubicin: compatible with NS and LR (no dextrose)
- Cubicin RF: compatible with NS but must only use sterile or bacteriostatic water for injection,
13
Q
Dapto drug interactions only one
A
- Increase muscle toxicity when used with statins
14
Q
Oxazalidinones: wht are the drugs, the MOA, and coverage
A
- Linezolid (Zyvox), Tedizolid (Sivextro)
- Bind to 50s ribosomal subunit inhibiting translation and protein synthesis
- Coverage similar to vanc but also cover all VREs
15
Q
Linezolid dosing, contraindications, warning, SEs, monitoring and notes
A
- No renal adjustment
- IV:PO 1:1
- Do not use within 2 wks of an MAO
- Warnings: duration related myelosuppresion (thrombocytopenia, anemia, leukpenia)
- Optic neuropathy when used for longer than 28 days
- Serotonin syndrome
- hypoglycemia
- Increased BP
- SEs: decreased platelets Hgb, WBC, Increased LFTs
- Monitor: HR, BP weekly CBC
- DO not shake linezolid suspension
16
Q
Linezolid and Redizolif drug interactions
A
- They are reversible monoamine oxidase inhibitors, avoid tyramine containing food and serotonergic drugs
- Linezolid can exacerbate hypoglycemic episodes, caution in patient receiving insulin or oral hypoglycemic drugs (sulfonylureas)
17
Q
Streptogrammin drug: MOA, coverage
What is it approved for?
A
- Quinupristin/Dalfopristin (synercid)
- binds to 50s subunit inhibiting protein synthesis
- Covers most gram +, including MRSA and E. Faecium (not faecalis)
- Complicated skin and soft tissue infections but not well tolerated so typically only used for VRE Faecium
18
Q
Synercid Notes
and Interactions
A
- Quinu/Dalfro
- Athralgias and Myalgias in up to 47% of pts
- Infusion reactions including edema and pain
- Hyperbilirubinmia, CPK elevation, Increased LFTs
- Notes
- D5W only
- admin via central line such a PICC to avoid phlebitis
- Interactions:
- weak 3A4 inhibitor it can increase levels of CCBs, cyclosporine, dofetilide and others
19
Q
Glycycline drug: MOA, coverage, and treatment approval
A
- Tigecycline (Tygacil)
- Binds to 30S subunit inhibiting protein synthesis
- Structurally related to tertracyclines
- Broad g+, including MRSA and enterococcus
- G-, bacteria, anaerobes and atypicals
- HAS NO ACTIVITY AGAINST the 3Ps (Pseudomonas, Proteus, Providencia)
- Complicated skin and soft tissue infections, intraabdominal infections, and CAP use is limited why?
20
Q
Tigecycline notes:
and DIs
A
- Tygacil
- Boxed warning increased risk of death, only use when absolutely have to
- Hepatotoxic, pancreatitis, photosensitiivty, teath discoloration in children <8
- Notes
- Do not use for blood stream infections: not enough concentration
- Reconstituted solution should be yellow-orange DC if not
- DI: increase INR in patients taking warfarin
21
Q
What are the polymyxins what are there MOA,
Coverage
A
- Colistimethate (sometimes called colistin) Coly-Mycin M
- inactive prodrug that is hydrolyzed to colistin. Cationic detergent and damages the bacterial cytoplasmic membrane causing leakage and cell death
- Polymyxins cover gram negative bacteria like (Enterobacter, E. Coli, Klebsiella, Pseudomonas, does not cover proteus
- Due to toxicity risk they are primarily used for MDR gram-negative pathogens in combination with another abx
22
Q
Coly-Mycin M
A
- CrCl<80 dose adjustment
- Solution for inhalation must be mixed immediately prior to administration
- Warnings:
- Dose dependent nephrotoxocity, neurotoxicity (dizziness)
- Notes:
- prodrug that is converted to colistin, assess dose carefully
- Avoid use with other nephrotoxic meds
- Neurotoxicity can result in respiratory paralysis from neuromuscular blockade
23
Q
Polymxyin B sulfate
A
Boxed warnings
- Dose dep nephrotoxicity
- Neurotoxicity
- Safety in pregnancy not established
- Only in hospital
- Neurotox can result in respiratory paralysis
Monitor renal function
1 mg = 10000 units of polymyxin B
24
Q
Polymyxin Drug interactions
A
- Other nephro drugs (AMGs, cisplatin, AmphoB)
25
Chloramphenicol MOA, and coverage
Notes as well
* Revesibly binds to 50S
* G+, G-, anaerobes, and atypicals
* Boxed Warnings
* Serious and fatal blood dyscrasias (aplastic anemia, pancypenia, may be reverisble
* Warniings:
* Gray syndrome with high serum concentrations
* G6PD deficiency
* Monitoring: CBC at baseline and every 2 days, LFTs, renal function, serum drug concentrations
26
Clindamycin MOA, coverage
* Lincosamide which reversibly binds to the 30S
* Covers aerobic and anaerobic g+ including (CAP MRSA) does not cover enterococcus or gram negative pathogens
27
Cleocin Notes
* Topical form
* No dosage adjustments in renal impairment
* Boxed warning
* C.Diff colitis
* Warning
* Severe or fatal skin rxn (SJS/TEN/DRESS)
* SEs:
* N/V/D
* Notes;
* An induction test (D-test) should be performed on S. Aureus that is susceptible to clindamycin but resistant to erythromycin a **flattened zone** between the disks (positive D test) indicates inducible clindamycin resistance and clindamycin should not be used
* Common uses: purulent and non-purulent skin infections, beta lactam alternative for dental abcess
28
Metronidazole and related meds: Which ones, MOA, coverage
* Metronidazole (flagyl) topical and vaginal, Tinidazole, Secnidazole
* cause loss of helical DNA structure and strand breakage resulting in inhibition of protein synth
* Metro covers: anaerobes and protazoal infections
* Effective for bacterial vaginosis, trichomoniasis, giardisis, amebiasis, C.Diff, and is used in combination regimens for intraabdominal infections
29
Tinidazole coverage
Secnidazole
* Acitivity limited to protozoa (giardiasis, amebiasis), trichomoniasis, and bacterial vaginosis
* Secnidazole only indicated for bacterial vaginosis
30
Metronidazole and Tinidazole notes
* Metro IV:PO 1:1, Take with food
* Boxed Warnings:
* Possible carcinogenic based on animal data
* Contraindications
* pregnancy 1st trimester, use of alcohol or propylene glycol-containing products during treatment or within 3 days of tx DC (disulfram reaction)
* Metro: use of disulfram within the past 2 wks
* Tinidazole: breastfeeding
* SEs: metallic taste, dark urine, SJS/TEN
31
Secnidazole (Solosec) Notes:
* Possibly carcinogenic
* SEs
* Vulvovaginal candidiasis, HA, N/V
32
Metro (flagyl) and Tinidazole drug interactions
* Metro Weak 3A4 and 2C9 inhibitor
* Tinidazole: minor substrate of 3A4
* Both should not be used with alcohol during and for 3 days after DCing
* Metronidazole (flagyl ) and potentially tinidazole, can increase INR in patients taking warfarin
33
Fidaxomicin
Every thing
Inhibits RNA polymerase resulting in inhibition of protein synthesis
It is used to treat C.Diff
* Dificid
* Warnings: Not effective for systemic infections
34
Rifaximin
Inhibits RNA synthesis by binding to DNA dep RNA polymerase, structurally related to Rifampin. Covers E.Coli
35
Rifaximin Indications and Notes:
* Travelers diarrhea, reduction of hepatic encephalopathy recurrence, IBS with diarrhea
* Not effective for systemic infections
* Used as salvage treatment for
36
Fosfomycin
MOA and Coverage
* Inhibits bacterial cell wall synthesis by inactivating the enzyme pyruval transferase. Covers, E.Coli (including ESBLs) and E.Faecalis (including VRE)
* A single dose regimen is used for uncomplicated UTIs (cystitis only)
* FEmale uncomplicated UTIs
37
Nitrofurantoin
Coverage MOA and notes
* Bacterial cell wall inhibitor it is used for uncomplicated UTIs (cystitis only. Covers E. COli, Klebsiella, Enterobacter, S. Aureus, and enterococcus (VRE)
* Macrobid
* Contrainfications:
* Renal impairment \<60: not enough urinary concentrations
* Warnings:
* hemolytic anemia (detected with a positive coombs test) use caution in patients with G6PD deficiency
* SEs:
* GI upset (take with food), brown urine discoloration (harmless)
38
Nitrofurantoin (Macrobid) Take aways
* DOC for uncomplicated UTIs,
* Do not use: Contraindicated in CrCl\<60
* Dosing
* Macrobid BID
* Macrodantin QID
* Counseling
* Take with food
* Can discolor urine
39
Topical Decolonization
What is it used for?
* Mupirocin nasal ointment (Bactroban)
* Used to eliminate staph (MRSA) colonization of the nares
