Flashcards in Pharm antimicrobials 3 Deck (39):
1
what are the nucleic acid synthesis inhibitors?
fluoroquinolones, metronidazole, rifamycin
2
what are the fluoroquinolones
-floxacin
ciprofloxacin, levofloxacin, moxifloxacin
3
fluoroquinolones mechanism
FLOCK OF SINNERS
-gyrating (inhibit DNA gyrase - topoisomerase II and IV)
- bactericidal
4
what must fluoroquinolones not be taken with?
antacids (divalent cations chelate oral quinolones_
5
fluoroquinolones spectrum
gram - rods of urinary and GI tracts including pseudomonas, neisseria, intracellulars, also some gram + (bug that would ruin a party! bring the party inside!) STDs, UTIs, GI and ab infections
6
side effects of fluoroquinolones
GI irritibility - vomiting, diarrhea (hang over), superinfections, skin rashes, headache, dizziness, tendonitis, prolonged QT
7
who is fluoroquinolones contraindicated in? why?
children and pregnant - hurt attachments to bones - damage cartilage (CHILDREN AND PREGNANT CAN'T DRINK!)
8
what are the only oral agents effective against pseudomonas?
levofloxacin and ciprofloxacin
9
metronidazole mechanism
forms toxic free radicals in bacterial cell that damage DNA - bactericidal, antiprotozoal
10
metronidazole spectrum
anaerobes BELOW the diaphragm - excluding actinomycetes and peptostreptococcus (get on the METRO with METROnidazole!)
covers C difficile!
also covers the protozoa (trichomonas, giardia, entamoeba histolytica)
11
what are the two drugs that cover c difficile?
metronidazole or vancomycin
12
what is used in triple therapy against h pylori?
metronidazole, clarithromycin, proton pump inhibitor
13
metronidazole side effects
disulfiram-like reaction (severe flushing, tachycardia, hypotension) with alcohol; headache, metallic taste
14
what are the rifamycins?
RIF-
rifampin, rifabutin, rifaximin
15
rifamycins mechanism
inhibit DNA-dependent RNA polymerase (inhibit RNA synthesis)
16
rifamycin spectrum
mycobacterium mostly, also gram + and gram - as adjunctive therapy
17
what are the 4 Rs of rifamycins?
1. RNA polymerase inhibitor
2. Ramps up microsomal cytochrome P-450 (BUT rifaBUTin does not)
3. Red/orange body fluids
4. Rapid resistance if used alone
18
rifamycin side effects
minor hypatotoxicity and drug interaction, orange body fluids
19
which rifamycin is preferred in HIV infection?
rifabutin! (less P-450)
20
what are the antituberculosis drugs?
isoniazid, pyrazinamide, ethambutol, rifamycins
21
isoniazid mechanism
inhibition of mycolic acid synthesis (large fatty acid in cell wall of mycobacteria)
22
what is the only agent used as solor prophylaxis against TB? and monotherpay for latent TB?
isoniazid for both
23
isoniazid side effects
hepatotoxicity, p-450 inhibition, drug induced SLE, vitamine B6 deficiency
24
what needs to be administered with isoniazid?
vit B6
25
pyrazinamide mechanism
unknown - prodrug that works best at acidic pH
26
pyrazinamide side effects
hyperuricemia, hypatotoxicity
27
which TB drug works the quickest for killing?
pyrazinamide
28
ethambutol mechanism
decreased carbohydrate polymerization of mycobacterium cell wall by blocking arabinosyltransferase
29
ethambutol side effects
neuropathy and optic neuritis (reversible)
30
what are the folic acid synthesis and reduction drugs?
sulfonamides and trimethoprim
31
sulfamethoxazole mechanism
inhibit dihydropteroate synthase which inhibits folate synthesis - bacteriostatic
32
when does sulfamethoxazole become bacteriocidal?
when combined with trimethoprim (act synergistically)
33
sulfamethoxazole spectrum
gram +, gram 0, nocardia, chlamydia - uncomplicated UTIs, pneumocystis pneumonia and toxoplasmosis
34
when is the trimethoprim/sulfamethoxazole combindation (bactrim) dangerous to give?
when taking warfarin because causes increased warfarin = increased risk of bleeding
35
sulfamethoxazole side effects
allergies,displace other drugs from albumin (warfarin)
36
trimethoprim mechanism
inhibits bacterial dihydrofolate reductase - bacteriostate
37
trimethoprim spectrum
UTIS, shigella, salmonella, pneumocystis jirovecii, pneumonia treatment and prophylaxis, toxoplasmosis
38
TMP/SMX bactrim use
TMPS:
T = resp tree; M = mouth, gram - GI tract; P = pee (UTI); S = syndrome - AIDS prevents PCP when CD4 under 200
39