Antifungal Drugs - Ch. 92

Question 1

Fungi

Answer 1

-Large and diverse group of micro-organisms
-Broken down into yeasts and moulds

Question 2

What is the term used for fungal infections?

Answer 2

Mycoses

Question 3

Where can fungal infections develop?

Answer 3

Normal flora of the skin, mouth, intestines, vagina (just like bacteria)

Question 4

There is a rise in which kind of fungal infections?

Answer 4

Opportunistic
-Broad-spectrum antibiotics causing less competition

Question 5

How are Mycotic (fungal) infections classified?

Answer 5

Superficial
Systemic

Question 6

Where do superficial mycotic (fungal) infections occur?

Answer 6

Integumentary
Mucous membranes

Question 7

What are systemic mycotic infections?

Answer 7

Can be life-threatening
May require prolonged drug therapy that can be toxic
Occur in immunocompromised hosts

Question 8

What is Candida albicans?

Answer 8

Common yeast

Question 9

Why are immunocompromised patients more likely to get a candida infection?

Answer 9

Antibacterial therapy, antineoplastics or immunosuppressents increase their risk

Question 10

What can result from a Candida albicans infection in an immunocompromised patient?

Answer 10

May result in overgrowth and systemic infections

Question 11

What are some parts of the body Candida albicans infects?

Answer 11

Mouth mucous membranes
Vagina

Question 12

What is is called when there is an infection of candida in the mouth?

Answer 12

Oral candidiasis or thrush

Question 13

What is it called when there is vaginal candidiasis?

Answer 13

Yeast infection

Question 14

What things can make you more susceptible to Candida infections?

Answer 14

Pregnancy
Diabetes Mellitus
Oral contraceptives

Question 15

What are dermatomycoses?

Answer 15

Tinea/ringworm
-Affects skin, nails and hair

Question 16

What are the main subgroups of antifungals?

Answer 16

Naturally occuring
Synthetic

Question 17

Which antifungals belong to the naturally occurring group?

Answer 17

Polyenes
Echinocandins

Question 18

Which antifungals belong to the synthetic group?

Answer 18

Azoles
Pyrimidines

Question 19

Examples of Polyenes?

Answer 19

Amphotericin B
nystatin

Question 20

Examples of Azoles?

Answer 20

Fluconazole
-miconazole, clotrimazole, ketoconazole,
itraconazole

Question 21

What can be used to treat systemic fungal infections?

Answer 21

Amphotericin B
Fluconazole, ketoconazole, itraconazole

Question 22

How is Amphotericin B administered?

Answer 22

SLOW IV injection
Lipid and non-lipid preparations

Question 23

How is Fluconazole, ketoconazole, itraconazole administered?

Answer 23

Multiple administration routes

Question 24

What is used to treat superficial fungal infections?

Answer 24

Nystatin
Azoles like fluconazole, ketoconazole, clotrimazole,
miconazole

Question 25

What find of superficial infections are treated via Nystatin?

Answer 25

Oral infections

Question 26

How is Nystatin administered?

Answer 26

Suspension should be swished in the mouth as long as possible before swallowing

Question 27

How is azoles for superficial infections administered?

Answer 27

PO/topical for vaginal candidiasis, skin infections (tinea)

Question 28

What is the mechanism of action of Polyenes: amphotericin B and nystatin?

Answer 28

Binds to sterols in cell membrane Makes hole sin fungi cell membranes Fungal cell death (mostly)

Question 29

What do higher concentrations of Polyenes do?

Answer 29

Bind to cholesterol of human cells to cause toxicities

Question 30

What is the mechanism of action of Azoles: fluconazole, ketoconazole, miconazole, clotrimazole?

Answer 30

Inhibit sterol-altering enzyme -Cyp P450 enzymes which cause less ergosterol in fungi membranes Leads to altered cell membrane Inhibits growth/kills cells

Question 31

What is the antifungal agent of choice for the treatment of severe systemic mycoses?

Answer 31

Amphotericin B -Azoles = alternative

Question 32

Amphotericin has many what?

Answer 32

Many adverse effects

Question 33

What are the main concerns (adverse effects) of amphotericin B?

Answer 33

Renal toxicity (K+ loss) Impairs hepatic functions

Question 34

Assess which functions before amphotericin B administration.

Answer 34

Liver and kidney functions

Question 35

What are the other adverse effects of Amphotericin B?

Answer 35

fever headache malaise hypotension muscle and joint pain chills dysrhythmias Nausea and vomiting Anorexia

Question 36

What is a patient pretreated with to reduce the severity of the amphotericin B infusion-related reactions?

Answer 36

Antipyretic (acetaminophen) Antihistamines (diphenhydramine) anti-emetics -test dose is given to assess the reaction

Question 37

Many azoles inhibit which enzymes?

Answer 37

Hepatic CYP enzymes

Question 38

What may the co-administration of two drugs metabolized by the hepatic system result in?

Answer 38

Competition for hepatic CYP enzymes -Higher levels of one of the drugs