Sulfonamides, Trimethoprim, Nitrofurantoin and Methanamine Flashcards Preview

POD Exam II > Sulfonamides, Trimethoprim, Nitrofurantoin and Methanamine > Flashcards

Flashcards in Sulfonamides, Trimethoprim, Nitrofurantoin and Methanamine Deck (17):
1

Sulfonamides MOA:

Competes with PABA for the enzyme dihydropteroate synthetase (PABA --> Folic Acid).

2

Sulfonamides excretion:

Excreted via glomerular filtration.

3

Sulfonamide ADRs (6):

- Anaphylaxis.
- Cutaneous reactions.
> Including SJS.
- Hematologic reactions.
- Hypersensitivity reactions.
- Nephrotoxicity.
- Kernicterus.
> When given in last months of pregnancy.

4

Sulfonamides spectrum of action (11):

G+:
- MRSA
- Strep
- Bacillus anthracis
G-:
- Piddly
- PEK
- Citrobacter
- Enterobacter
Other:
- Chlamydia trachomatis
- Toxoplasma gondii
- Plasmodium falciparum
- Nocardia

5

Sulfonamides mechanism of resistance:

- Overproduction of PABA.
- Structural change in dihydropteroate synthetase.
- Decreased permeability of the bacteria to the drug.

6

Indications for sulfonamides (6):

- Acute uncomplicated UTI.
- Pneumocystis carinii.
- Nocardosis.
- Malaria.
- Rheumatic fever prophylaxis.

7

Trimethoprim MOA:

Inhibits dihydrofolate reductase which prevents the formation of tetrahydrofolic acid.

8

Trimethoprim ADRs (4):

- Cutaneous reactions.
- GI reactions.
- Hematologic reactions.
- Caution in pts with possible folate deficiency.

9

Trimethoprim spectrum of activity

G+:
- Staph
- Strep
- Bacillus anthracis
G-:
- Piddly
- PEK
- Citrobacter
- Enterobacter
Other
- Pneumocystis carinii (with dapsone)

10

Indications for trimethoprim:

- Acute uncomplicated UTI.
- Recurrent UTI prophylaxis.
- Traveler's diarrhea.

11

Trimethoprim/sulfamethoxazole (bactrim) indications:

- UTI.
- RTI.
- GI infections.
- STDs.

12

SMZ/TMP (bactrim) drug interactions:

- Warfarin.
- Methotrexate.

13

Nitrofurantoin ADRs (6):

- Hypersensitivity.
- Hematologic reactions.
- Hepatotoxicity.
- Peripheral neuropathy.
- GI reactions
- Pulmonary reactions

14

Nitrofurantoin spectrum of activity

G+:
- Staph aureus
- Staph saprophyticus
- Enterococcus
G-:
- E. coli
- Klebsiella pneumonia
- Citrobacter spp.
- Enterobacter aerogenes

15

Indications for nitrofurantoin:

- Acute uncomplicated UTI tx.
- UTI prophylaxis.

16

Methenamine MOA:

At urine pH hydrolyzed to formaldehyde which kills by denaturing proteins.

17

Methenamine ADRs:

- Hypersensitivity
- Hemorrhagic cystitis
- GI reactions
- Avoid in hepatic insufficiency
- Renal failure