Antifungals/Antivirals Flashcards
1
Q
Name all the antifungals
A
Antimetabolites azoles polyenes griseofulvin allyamines glucan synthesis inhibitors others
2
Q
What are good targets for antifungals?
A
- ergosterol
- DNA
- microtubules
- cell wall
3
Q
Allyamines
- MOA
- Spectrum
- SE
A
- inhibits ergosterol biosynthesis via inhibition of squalene epoxidase
- acts on dermatophytes
- SE: usually transient and mild (GIT/skin)
4
Q
what are the allyamines pharmocokinetics?
A
- highly lipophyllic
- hepatic metabolism
- renal excretion
- readily absorbed by the body fat and epidermis of the skin
- remain on skin at therapeutic concentrations even after application is stopped
5
Q
Azoles
- MOA
- SE
- Spectrum
A
- inhibition of cytochrome P450 dependent 14-sterol de-methylase
- SE: GIT, anorexia, hepatotoxicity, suppression of steroid production, teratogenic
- broad: aspergillus, dermatophytes, yeast and yeast-like fungi
6
Q
what are the pharmacokinetics of azoles?
A
ketoconazole and itraconazole: -weak bases (require acid environment to work) -lipophyllic -highly PPB -hepatic metabolism -excretion in bile and urine Fluconazole -not affected by gastric pH -water soluble -minimal PPB -minimal metabolism -80% excrete in kidneys unchanged
7
Q
Polyenes
- MOA
- spectrum
- SE
A
- binds to ergosterol and disrupts osmotic integrity of the membrane
- spectrum: broad but not dermatophytes
- nephrotoxic
8
Q
What are the pharmacokinetics of polyenes?
A
Pharmacokinetics:
- poorly water soluble
- little absorbtion from GIT
- encapsulated in lipid coat/lipid complex which increases uptake into tissues other than the kidney
- tend todeliver drugs to areas which are lipid rich sucha s cell membrane
9
Q
Glucan synthesis inhibitiors
- MOA
- Spectrum
- SE
A
- depletion of beta (1,3) glucans in the cell wall
- inhibit beta (1,3) glucan synthase
- mannoproteins not held in place and the whole thing falls apart
- candida and aspergilus
- minimal SE
10
Q
What are the pharmacokinetics of Glucan synthesis inhibitors?
A
- water soluble
- highly PPB
- plasma clearance due to redistribution
11
Q
Antimetabolites
-MOA
-spectrum
SE
A
- disrupts protein synthesis
- candidia and cryptococcus
- SE are minimal
12
Q
What are the pharmacokinetics of antimetabolites?
A
- excreted unchanged by kidneys
- often combined with amphotericin B (synergistic)
13
Q
Griseofulvin
- MOA
- spectrum
- SE
A
-selectively depositied in newly formed keratin
-inhibits mitosis and disorganises the spindle mircotubule
-narrow: all dermatophytes
SE: teratogenic and idiosyncratic reaction in cats
14
Q
What are the pharmacokinetics of griseofulvin?
A
- poorly water soluble
- hepatic metabolism and elimination
15
Q
Aciclovir
A
- inhibits viral DNA polymerase
- high specificity for herpes complex
- use for FIV and viral eye infection
