Anti-Fungal chemotherapy Flashcards
What is candiasis?
infection caused by yeast Candida albicans - causes thrush (oral or vaginal)
What does ringworm cause?
Athletes foot and dandruff - can be caught from pets
- treated with ketaconazole
What is blastomycosis?
affects lungs of young men
What is pneumocystis pneumonia treated with?
co-trimoxazole
How does colonisation of a fungal disease occur?
inhalation of spores and so common among agricultural workers
What are the 2 targets for anti-fungal drugs?
cell wall (as we don't have one) cell membrane ergosterol (we have cholesterol)
how does amphotericin B work?
it’s amphoteric and binds to ergosterol in cell membrane forming pores, causing leak due to high osmotic pressure
what is amphotericin B used to treat?
oral infections when given locally and systemic infections when given IV
Why is amphotericin B dangerous?
as it is toxic to kidneys although lipid based formulations are less toxic
Nystatin is similar in structure and mechanism of action to amphotericin B, in what formulations is it available?
creams and ointments
name a drug which inhibits squalene epoxidase which is an enzyme in ergosterol formation:
terbinafine - used topically or orally
WHO essential med
squalene to ergosterol needs many enzymes inc CYTP450 14a demethylase, which group of drugs work by inhibiting this?
azoles and triazoles;
- ketaconazole, miconazole, voriconazole, posaconazole
Why can polyenes such as Nystatin, not be used with azoles?
because nystatin relies on sterol binding in order to work
which azalea is used to treat cats and guinea pigs?
itraconazole
What is the penicillin of antifungals? and why is it called this?
echinocandin - prevent cell wall cross linking
toxic to embryos and liver
