DNA damaging ABs

Question 1

what are the DNA damaging Abs

Answer 1

quinolones
nitroflurantoin
metronidazole
methenamine

Question 2

all quinolone end in what?
what is the warning about quinolone and what not to take them with and why?
quinolones are effective against gram - or gram +

Answer 2

all quinolones end in (floxacin)
DO NOT take quinolone with MILK, bc the cations in milk chelate quinolones and DEC absorption
quinolones= BOTH gram - and gram + !!!

Question 3

MoA of quinolones

cidal or static?

Answer 3

quinolones inhibit DNA replication through poisoning of DNA gyros A
CIDAL!
no note on selectivity

Question 4

Clinical uses of Quinolones:

what specific bacteria are quinolones used against?

Answer 4

UTIs, RTIs, 2nd line of defense for TB and anthrax

Ciprofloxacin and Levofloxacin= Pseudomonas aeruginose

Question 5

what mechanisms are making bacteria resistant to Quinolones?

Answer 5

1. mutations in gyrase or topoisomerases target
2. inc efflux pumps
3. altered porins (gram -)

Question 6

Moxifloxacin is a what generation Quinolone?
what is it used for?
what is the specific use of Moxifloxacin?

Answer 6

Moxifloxacin is a 4th generation for gram +
tx for RTI,
USED to treat Penicillin resistant S pneumonia!!

Question 7

General Pharmacokinetics of quinolones including absorption, distribution, excretion, toxicity

Answer 7

Quinolones are taken orally (NOT W MILK)
renal excreted (except Moxifloxacin)
Tox: mild, NVD, peripheral neuropathy

Question 8

What Quinolone do you avoid in children (what generation) and why

Answer 8

Avoid Ciprofloxacin in children (2nd gen) bc it has potential to rupture tendons

Question 9

What AB causes DNA damage by formation of O2 free radicals subsequent to reduction of nitro group?
what is the only tx used for this drug?

Answer 9

nitrofurans- nitrofurantoin

only used for tx of UTI

Question 10

Nitrofurans are NOT effective against what>

what is the spectrum of nitrofurans?

Answer 10

Nitrofurans not effective against P aeruginosa

Nitrofurans are effective against Gram - and Gram + !

Question 11

Pharmokinetics of Nitrofuran: absorption, distrib

Answer 11

Nitrofuran well absorbed orally, rapidly metabolized, and renal excretion

Question 12

what is the CONTRA for nitrofuran?

Answer 12

CONTRA= poor renal function, low creatinine clearance,

Question 13

toxicity of nitrofuran

Answer 13

acute pleural effusions, pulmonary fibrosis, urticaria

Question 14

What Ab causes DNA damage, is rarely used for prophylaxis and breaks down to form formaldehyde?
How do you inc selectivity of this AB?
MoA of DNA damage?

Answer 14

Methenamine
INC selectivity by acidifying urine
denatures proteins

Question 15

Clinically Methenamine is used for what, is not effective against what? and what does pt need to do while on methenamine?

Answer 15

Methenamine is effective against GRAM NEG!
Not effective against pseudomonas
Make sure pt drinks lots of water!!

Question 16

What is a prodrug that is used for Anaerobic infections?

Answer 16

Metronidazole

Question 17

Metronidazole is a pro drug used for anaerobic infections, is it static or tidal? gram - or gram +?
resistance how?

Answer 17

Metronidazole is a pro drug that is CIDAL! effective against BOTH gram - and gram + anaerobes!
resistance to metronidazole is due to DEC activation bc PRO DRUG!

Question 18

Pharmacokinetics of Metronidazole?

Answer 18

Absorption: orally, penetrates CNS, excreted renally, mild toxicities: prevents metabolism of alcohol

Question 19

Big CONTRA for pts on metronidazole?

Answer 19

DO NOT CONSUME ALCOHOL!