Antifungals ALLYLAMINES

Question 1

Griseofulvin is a metabolic derivative of what?

Answer 1

Penicillium Griseofulvum

Question 2

Griseofulvin is classically used for the treatment of what?

Answer 2

Dermatophytes

Question 3

Does Griseofulvin have an activity against yeast and molds?

Answer 3

NONE

Question 4

Is Griseofulvin fungicidal or fungistatic?

Answer 4

FUNGISTATIC

Question 5

Where does Griseofulvin bind?

Answer 5

It binds tubulin and
microtubule- associated proteins (MAPS) along the polymerized microtubules–> suppressing formation of the mitotic spindle at the G2/M phase of the cell cycle (THIS INHIBITS cell division and forces the cell to undergo apoptosis)

Question 6

Is Griseofulvin water soluble or insoluble?

Answer 6

it is water insoluble

Question 7

Does Griseofulvin have a low or a high bioavailability?

Answer 7

LOW

Question 8

Where does drug absorption happen in griseofulvin?

Answer 8

Duodenum

Question 9

Better absorption of griseofulvin can occur either when coated with?

Answer 9

Polyethylene glycol or on coadministration with fatty meals

Question 9

Griseofulvin is characterized by?

Answer 9

Its accumulation in the keratin-producing tissues, where it is adherently bound to the newly formed keratin. Rendering it resistant to fungal penetration

Question 10

What enzyme is responsible for the accumulation of Griseofulvin in the liver?

Answer 10

6-desmethyl enzyme

Question 11

How is Griseofulvin eliminated from the body?

Answer 11

Through the kidney in the form of metabolites

Question 12

Griseofulvin remains the first line of treatment for?

Answer 12

Tinea capitis caused by Microsporum species

Question 13

Griseofulvin

Answer 13

The cutaneous elimination of the drug is slower than its elimination from plasma, allowing for extended drug activity even after its discontinua- tion.

Question 14

Griseofulvin

Answer 14

• has higher efficacy compared to terbinafine
• similar efficiency yet lower cost compared to itraconazole and fluconazole

Question 15

what is the only FDA-approved treatment for pediatric onychomycosis?

Answer 15

Griseofulvin (though its efficacy is limited to dermatophytes only)

Question 16

What are the allylamines? (TN)

Answer 16

Terbinafine and naftifine

Question 17

Is terbinafine available in topical or oral or both?

Answer 17

BOTH

Question 18

Is naftifine available for topical or oral or both?

Answer 18

TOPICAL

Question 19

Are allylamines fungistatic or fungicidal?

Answer 19

BOTH-
it has antifungal activity against Candida species (fungistatic)
dermatophytes (fungicidal)

Question 20

What is the mechanism of action of allylamines?

Answer 20

inhibit squalene epoxidase enzyme (responsible for catalyzing squalene precursors into ergosterol)
They act through the suppression of ergosterol synthesis

Question 21

In allylamines, the resultant deficiency of ergosterol is responsible for what?

Answer 21

FUNGISTATIC effect

Question 22

In allylamines the buildup of squalene accounts for what?

Answer 22

FUNGICIDAL ACTIVITY

Question 23

In addition to Naftifine antifungal activity what are the other mechanism of action?

Answer 23

1) Antibacterial activity (gram-positive and gram-negative)
2) Anti-inflammatory properties secondary to its ability to suppress the synthesis of leukotrienes and prostaglandins

Question 24

Naftifine has antiinflammatory properties secondary to its ability to suppress what?

Answer 24

synthesis of leukotrienes and prostaglandins

Question 25

Describe the pharmacokinetics of Naftifine

Answer 25

>the lipophilic properties of naftifine account for its efficient penetration through the stratum corneum >therapeutic drug levels can persist in stratum corneum up to 5 days following a single application >only 3% to 6% of the applied drug can be systemically absorbed

Question 26

What are the clinical indications of naftifine?

Answer 26

1) Interdigital tinea pedis 2) Tinea cruris 3) Tinea corporis 4) tinea versicolor 5) Candida infections

Question 27

Naftifine is commercially available as what?

Answer 27

1% gel or cream

Question 28

How do you give naftifine?

Answer 28

once-twice daily for 2-6 weeks (sa table) or 2-4 weeks ba

Question 29

What are the side effects of naftifine?

Answer 29

MINOR LANG dryness pruritus local irritation erythema

Question 30

What is the mechanism of action of terbinafine?

Answer 30

1) It works through the suppression of squalene epoxidase enzyme, blocking the formation of ergosterol