Pharm 4 Exam 2 & 3 Flashcards Preview

Semester 1 > Pharm 4 Exam 2 & 3 > Flashcards

Flashcards in Pharm 4 Exam 2 & 3 Deck (32):
1

Components of fungi cell walls

- Chitin
- Egesterol
- Beta Glucans
- Structural Proteins

2

Ergosterol Pathway

The CP450 enzyme 14a-sterol demethlase converts lanosterol into ergoesterol

3

Subcutaneous and systemic Mycoses

- Azoles
- Echinocandins
- Polyenes
- Prymadine Antifungals

4

MOA for Azoles

Inhibition of CELL MEMBRANE BY Inhibiting ergoesterol synthesis by direct inhibition of 14a demythlase.

5

Side effects of Azoles

- Mild GI
- Hepatotoxicity (rarely)

6

Contraindications of Azoles

None

7

MOA of Echinocandins

Inhibition of fungal CELL WALL synthesis, which weakens the wall. By inhibition of beta 1-3 glucan synthase.

8

Contraindications of Echinocandins

None

9

Side Effects of Echinocandins

- Mild GI N/V
- Infusion reactions

10

MOA of Polyenes

Polyenes bind to ergosterol creating pores within the CELL MEMBRANE, causing an escape of H+ and K+ leading to cell death.

11

Contraindications of Polyenes

Renal dysfunction

12

Side Effects of Polyenes

- Nephrotoxicity
- Infusion reactions
- Electrolyte imbalances

13

Define the depletion theory of the interaction between Azoles an Polyenes.

Preexposure to Azoles depletes the fungal cells of ergosterol, leading to fewer targets for polyene, resulting in antagonism

14

Define the enhancement theory of the interaction between Azoles an Polyenes.

Preexposure to Polyene leads to the formation of pores that facilitate greater access for azoles to the intercellular space leading to an additive effect

15

Pyrimidine Antifungals MOA

It is taken up by cytosine permeases which are specific to fungal cells. It is converted to 5FU then 5FdUMP which inhibits Thymine synthase leading to termination of DNA synthesis and cell division.

16

Pyrimidine Contraindications

- Pregnancy

17

Side Effects of Pyrimidine Antifungals

- GI abd pain N/V
- Risk of infection

18

Agents used for cutaneous mycoses

- Griseofulvin
- Terbinafine

19

Griseofulvin MOA

- Deposited in keratin precursor cells in the skin
- It is then taken up by fungal cells and inhibits microtubule polymerization
- Inhibits mitosis
- New skin and hair is then resistant to infection

20

Griseofulvin contraindications

Pregnancy

21

Griseofulvin side effects

- CNS; headache, peripheral neuropathy
- Dermatologic; skin rashes

22

Terbinafine MOA

Inhibits the conversion of Squalene to Lanosterol via inhibition of squalene monoxidase. (Lanosterol is then converted to Ergosterol)

23

Terbinafine contraindications

Pregnancy

24

Terbinafine side effects

- Steven-Johnson syndrome
- Toxic epidermal necrolysis
- Liver failure
- Neutropenia and lymphopenia

25

Quinolones MOA

- Act to inhibit the stage in which merozoites are released from the liver back into the blood within the erythrocyte

26

Quinolones Side effects

- GI, Headache, Pruritus
- Retinopathy, Ototoxicity, Arrhythmia

27

Metronidazole MOA

Is a prodrug which is activated by ferredoxin. Reduction results ini toxic products and free radicals which damage DNA. Effective on anaerobic bacteria.

28

Metronidazole contraindications

- Ethanol (acetyldehyde)
- Pregnancy

29

Metronidazole side effects

- GI nausea
- Metalic Taste
- CNS toxicitiy (encephalopathy or seizure)
- Neutropenia
- Pancreatitis
- Peripheral neuropathy
- Hepatitis

30

Antiprotozoals (Diamidines) MOA

- Penertates through parasite specific pores
- Bind to ferriprotoporphyrin
- Inhibit DNA replication
- Inhibits topoisomerase II

31

Antiprotozoals (Diamidines) contraindications

Highly toxic but infections are life threatening

32

Anitprotozoals (diamidines)Side effects

- Hypotension
- Glucose abnormalities
- Renal dysfunction
- Hepatic dysfunction