E3 Antifungals

Question 1

4 major classes of Antifungals

Answer 1

1. Polyenes (nystatin & amphotericin B
2. Pyrimidine (flucytosine)
3. Azoles (fluconazole)
4. Misc. Agent (grisefulvin)

Question 2

Nystatin indication

Answer 2

Treatment of superficial candida infections of mouth (thrush), oral mucosa, vaginal, & skin

-Never for systemic infection

Question 3

nystatin route

Answer 3

Creams, powders, TOPICAL, vaginal
TOO TOXIC for parental (IV)

Question 4

SE of nystatin

Answer 4

Not alot
Mild skin irritation
N/V/D when taken orally
Poor GI absorption

Question 5

Indication of Amphotericin B

Answer 5

Agent of choice for most systemic mycoses

Question 6

MOA of Amphotericin B

Answer 6

Binds to ergosterol in fungal cell membranes & causes them to become leaky and destroys cell wall of the fungus

Question 7

Amphotericin B route

Answer 7

PO
Parental (IV)- must dilute & admin slowly
NOT TOPICAL

Question 8

Nursing considerations for Amphotericin B

Answer 8

-Monitor BUN/Creatinine
-Pt must be on cardiac monitor with frequent vitals
-Given every other day for several months

Question 9

Pretreatment of Amphotericin B with ______ to decrease infusion symptoms of _______

Answer 9

diphenhydramine, acetaminophen, or aspirin

fever, pain, nausea, headache

Question 10

Amphotericin B has synergistic effect when given with _____

Answer 10

flucystosine

Question 11

MOA of flucytosine

Answer 11

inhibits fungal DNA synthesis

Question 12

Indications of flucytosine

Answer 12

allows for a lower dose of Amphotericin B to be used (decrease SE)

Question 13

What are the 5 azoles

Answer 13

1. Ketoconazole
2. Miconazole
3. Clotrimazole
4. Itraconazole
5. Fluconazole

Question 14

MOA of the azoles

Answer 14

Interrupts the integrity of the cell wall by interfering with the synthesis of ergosterol

Question 15

Indications of azoles

Answer 15

Used for both superficial and less serious systemic fungal infections

Question 16

SE of azoles

Answer 16

-Topical may cause redness, burning, itching
-Systemic- severe GI upset N/V/D & liver toxicity (look for jaundice & abdominal pain

Question 17

Administration of azoles

Answer 17

-Take with food to minimize SE
-For oral separate at least 2 hours from antacids and drugs that decrease stomach acid

Question 18

Advantages of fluconazole

Answer 18

-Rapidly and completely absorbed when given orally, able to reach bones, CNS, eyes, respiratory, and urinary tract
-Much less toxic than Amphotericin B with fewer SE

Question 19

Disadvantages of fluconazole

Answer 19

Narrow spectrum
Many drug interactions (CYP450 path)

Question 20

Nursing implications of fluconazole

Answer 20

-Do not mix IV fluconazole with other meds
-Monitor coags for pts on warfarin
-Watch for hypoglycemia for pts w/ sulfonylureas
-Increases Haldol and Dilantin levels

Question 21

MOA of Grisefulvin

Answer 21

-Inhibits fungal mitosis
-Binds to keratin
-Does not effect the cell wall or membrane

Question 22

SE of Grisefulvin

Answer 22

-Bone marrow suppression
-Rash
-CNS changes
-N/V/D
-Anorexia

Question 23

Indications of Grisefulvin

Answer 23

Resistant dermatophyte infection of scalp, skin, and nails

Question 24

What Antifungals can be given topically?

Answer 24

1. Nystatin
2. Flucytosine?
3. Azoles
4. Grisefulvin

Question 25

What Antifungal CAN NOT be given topically?

Answer 25

Amphotericin B