Nucleic Acid Synthesis Inhibitors

Question 1

3 general indirect nucleic acid synthesis inhibitors

Answer 1

Sulfonamides
Trimethoprim
Pyrimethamine

Question 2

Sulfonamides are

Bacteriostatic/Bactericidal?

Answer 2

Bacteriostatic

Question 3

Sulfonamides spectrum

S. E. H. K. S. S. E. T. PJ. VC. N. C.

Poor activity against______

Answer 3

Strep pyogenes, E. coli. H influenza, Klebsiella, salmonella, shigella, Enterobacter, toxoplasma, p jiroveci, vibrio cholera, nocardia, chlamydia

Poor against anaerobes

Question 4

Sulfonamides inhibit what enzyme?

Answer 4

Dihydropteroate synthase

Question 5

Sulfonamides are metabolized by _________and _________ in the liver.

Answer 5

acetylation and glucuronidation

Question 6

Sulfonamides are ____soluble/insoluble in acid urine

Answer 6

Insoluble - drink plenty of water

Question 7

What class of drugs cause crystalluria?

Answer 7

Sulfonamides

Question 8

Oral sulfonamides (4)

Answer 8

Sulfisoxazole, sulfadiazine, sulfamethoxazole, sulfadoxine

Question 9

Oral non-absorbable agents (1)

Answer 9

Sulfasalazine

Question 10

Topic sulfonamide agents (3)

Answer 10

Sulfacetamide
Mafenide
Silver sulfadiazine

Question 11

Drug(s) of choice to treat PCP in AIDS patients

Answer 11

Sulfamethoxazole and trimethoprim (cotrimoxazole)

Question 12

Sulfonamide in combo with ______ to treat Malaria

Answer 12

Sulfadoxine & pyrimethamine

Question 13

Sulfonamide used with _______ to treat toxoplasmosis?

Answer 13

Sulfadiazine & pyrimethamine

Question 14

Sulfapyridine is combined with __________ for treatment of ulcerative colitis and rheumatoid arthritis

Answer 14

5-aminosalicylic acid

Question 15

Sulfonamide used with _______ to treat P. jiroveci pneumonia

Answer 15

Sulfamethoxazole & trimethoprim

Question 16

Sulfonamide used to treat eye infections used topically

Answer 16

Sulfacetamide

Question 17

Mafenide can cause ______ and its use should be limited in burn patients

Answer 17

Metabolic acidosis

Question 18

Topical sulfonamide that release silver ions to exhibit anti-microbial action

Answer 18

Silver sulfadiazine

Question 19

Silver sulfadiazine is used in _________and preferred over mafenide for preventions of infection

Answer 19

Burn dressings and ulcers

Question 20

Trimethoprim inhibits which enzyme?

Answer 20

Dihydrofolate reductase

Question 21

Trimethoprim is used best to treat ______ because it concentrates in ____

Answer 21

Acute UTI’s because it’s acidic

Question 22

In someone with G6PD deficiency taking sulfonamides, they should be careful of ____.

Answer 22

Hemolysis

Question 23

Fixed dose combination of trimethoprim and sulfamethoxazole is called____?

Answer 23

Cotrimoxazole

Question 24

Spectrum of Cotrimoxazole

Answer 24

S aureus (MRSA strains) 
S pneumonia
H influenzae
Klebsiella pneumonia
E. Coli
Salmonella
Shigella
Toxoplasma 
P. jiroveci

Question 25

Dose ratio of cotrimoxazole

Answer 25

5:1

Question 26

Therapeutic Uses of Cotrimoxazole

Answer 26

``` UTIs DoC in Nocardia DoC in P. jiroveci RTIs Typhoid fever Bacterial diarrhea ```

Question 27

Resistance to sulfamethoxazole (3 ways)

Answer 27

Overproduction of PABA Lower affinity dihydropteroate synthase Impair permeability

Question 28

Direct inhibitors of nucleic acid synthesis

Answer 28

Quinolones | Fluoroquinolones

Question 29

Nalidixic acid is active against

Answer 29

``` Gram - bacteria E. Coli Proteus Klebsiella Shigella ```

Question 30

Topoisomerase IV mechanism? Inhibited by?

Answer 30

Separates replicated chromosomal DNA into the respective daughter cells. Fluoroquinolone

Question 31

Binding of Fluoroquinolone to both the enzymes and DNA forms a complex that _____________________.

Answer 31

Inhibits the resealing step and can cause cell death by inducing cleavage of DNA

Question 32

Fluoroquinolones should be taken ____hours before and ____hours after _______products

Answer 32

2 hrs; 4 hrs; cation containing

Question 33

You should reduce dose of fluoroquinolones in renal dysfunction except

Answer 33

Moxifloxacin

Question 34

2 fluoroquinolones used in typhoid fever

Answer 34

Ciprofloxacin | Levofloxacin

Question 35

Fluoroquinolones are used in skin, soft tissues and bone infection except

Answer 35

Norfloxacin

Question 36

3 respiratory fluoroquinolones

Answer 36

Levo, Gemi, and Moxifloxacin

Question 37

Plasma concentrations of theophylline, warfarin are increased by 2 FQs

Answer 37

Ciprofloxacin | Ofloxacin

Question 38

In terms of bacterial resistance, ________ can inactivate Ciprofloxacin

Answer 38

Aminoglycoside acetyltransferase