Therapeutics Flashcards
(26 cards)
Antifungals: mechanisms of action (4)
- -Echinocandins: inhibit cell wall synthesis
- -Azoles: inhibit sterol synthesis
- -Amphotericin: cytoplasmic membrane damage
- -Flucytosine: inhibits DNA synthesis
Antifungals: holes in coverage (5)
- -Fluconazole: C. glabrata, C. kruseii, Aspergillus, Fusarium, Scedosporium, Zygomyces (very rarely C. albicans can be R if Pt has seen a lot of fluconazole previously)
- -Posaconazole: Scedosporium prolificans
- -Voriconazole: Scedosporium prolificans, Zygomyces
- -Echinocandins: C. parapsilosis, C. guillermondi, now concern for some C. glabrata, Cryptococcus, maybe problems w/ environmental fungi; no activity w/ Fusarium, Scedosporium, Zygomyces
- -Amphotericin B: C. lusitanea, Aspergillus terreus, Scedosporium prolificans, maybe Fusarium and maybe Scedosporium apiospermum
Antifungals: side effects (6)
- -AmphoB (side effects much less with liposomal form): nephrotoxicity, infusion related reaction (chills, rigors, malaise, N/V, hypotension), arrhythmias, hypoK and hypoMg, normocytic anemia
- -Ketoconazole: N/V, rarely hepatotoxicity, gynecomastia (blocks cortisol secretion), not absorbed if taken w/ PPI (needs acid, often tell to take w/ soda)
- -Fluconazole: N/V, hepatitis
- -Itraconazole: N/V, hepatitis, IV form can cause renal failure, not absorbed well if taken w/ PPI
- -Voriconazole: N/V, hepatitis, ocular toxicity, with long term (>6mo) use can get skin cancers and fluoride excess which leads to periostitis (sx is pain in long bones)
- -Flucytosine: N/V/D, bone marrow suppression, hepatotoxicity
Live immunizations (4)
- -intranasal influenza
- -MMR
- -Varicella
- -Zoster
Influenza vaccines and indications
- -high-dose: great immunogenicity, an option if >65
- -live-attenuated: healthy people age 2-49 including health care workers (unless they care for severely immunocompromised patients in isolated environments)
- -trivalent inactivated: for everyone else
HPV vaccine indications
- -boys and girls age 11-12 (can give as early as 9)
- -can give catch up until age 26 (for women) or 21 (for boy, but up to age 26 for high risk boys)
- -not recommended in pregnancy (due to limited data)
- -side effects: low grade fever in 1/10 and real fever in 1/65
MRSA treatment (9)
1) Vancomycin: standard of care
2) Dapto: approved for bacteremia and R sided endocarditis
3) Quinupristin-dalfopristin: bacteriostatic, active against E. faecium but not E. faecalis, requires a central line
4) Telavacin: bactericidal, approved for SSTIs, active against MRSA, VRSA (ADRs: increased Cr and taste disturbance)
5) Ceftaroline: bactericidal, studied in SSTI, PNA, similar gram- to CTX (no activity for Pseudomonas, ESBL, Acinetobacter
6) Linezolid
7) Clindamycin
8) Doxycycline
9) TMP-SMX
Enterococcus faecalis bacteremia
Ampicillin with gent or CTX
Stenotrophomonas treatment
Preferred: TMP-SMX
Alternative: ceftaz, CTX, amp-sulb, tic-clav (not pip-tazo), tetracyclines, fluoroquinolones
Bacteria predictably resistant to carbapenems (4)
MRSA, E. faecium, Stenotrophomonas, carbapenemase* producing organisms (Pseudomonas, E. coli, Acinetobacter, Citrobacter, Enterobacter, Salmonella/Shigella, Klebsiella,..PEACES K)
*Detected by modified Hodge test
Aminoglycoside spectrum (7)
peritonitis from GI source (with metronidazole),
plague
tularemia
brucellosis (with doxy)
Bartonella endocarditis (with CTX and doxy)
Enterococcal and Staph endocarditis (some cases), Mycobacterial infections
Fluoroquinolone differences
enteric gram-: cipro
anaerobic GNRs: moxi
MDR TB: moxi or levo (cipro likely inferior)
Strep pneumo: 4.5% resistance with cipro, 1% with levo and moxi
Random TMP-SMX spectrum (7)
Listeria, Stenotrophomonas, Cyclospora, Isospora, Coxiella, M. marinum, Tropheryma whipplei
Tetracycline spectrum (12)
spirochetes (Leptospirosis, Lyme, relapsing fever, syphilis) Rickettsia Ehrlichia atypical pneumonia pathogens LGV granuloma inguinale Actinomyces Nocardia MRSA Brucella Tularemia Whipple’s disease
Don’t give with colchicine
Macrolides
Polymyxin B/E
Use: PEACES K, no gram+ activity; always use with combination therapy
Synergy for combination therapy: AGs, carbapenems, tigecycline
ADRs: ATN in 8%, neurotoxicity
Clindamycin resistance
- -concern for inducible resistance if R erythromycin and S to clindamycin; do D test
- -increasing B. fragilis resistance
Daptomycin see-saw
For MRSA when given with ampicillin R to one make it more susceptible to the other (7/7 cases with difficult to clear bacteremia cleared it on both)
ADRs: eosinophilic PNA, rhabdo
Rifampin uses (3)
Monotherapy: N. meningitides ppx
Others (combination therapy)
–Staph aurues and Staph epi w/ prosthetic material
–Brucella, TB, Leprosy
Metronidazole holes in anaerobic coverage (4) and ADRs (4)
P. acnes, Peptostreptococcus, Eikenella, Actinomyces
ADRs: metallic taste, disulfiram reaction, aseptic meningitis, peripheral and optic neuropathy (prolonged use)
Rifampin and rifabutin DDIs (induce p450)
Effect on other drugs:
Reduces the following: atovaquone, dapsone, caspofungin (increase to 70mg daily if rifampin), azoles, PIs (reduces; cannot use with rifampin; if using rifabutin then decrease rifabutin dose), NNRTIs, integrase inhibitors, clarithromycin, cyclosporine, tacrolimus, sirolimus, coumadin, digoxin, methadone, many anticonvulsants
Reduce rifabutin dose when given with azoles and PIs (increased with EFV)
Protease inhibitors DDIs (inhibit p450)
Effect on other drugs
Increases the following: rifampin, rifabutin, ketoconazole, itraconazole, anticonvulsants, statins (avoid simvastatin and lovastatin, atorvastatin ok with monitoring and pravastatin likely best with monitoring), midazolam, ergotamines, NNRTIs
NNRTI DDIs (induce p450)
Effect on other drugs
Reduces the following: rifampin, rifabutin, ketoconazole, itraconazole, anticonvulsants, statins (may need to increase doses), midazolam, ergotamines, PIs, echinocandins (increase caspofungin to 70mg daily with RFV or NVP)
Avoid etravirine with unboosted PI or boosted ATV
Drugs that effect cyclosporin, tacrolimus, sirolimus levels
Decreases immunosuppressants: rifampin
Increases: azoles (ketoconazole > vori/posaconazole > itraconazole > fluconazole) and macrolides (erythromycin > clarithromycin > azithromycin)
