T3-Antifungals Flashcards
What is the MOA of amphotericin B?
Binds to the fungal membrane by binding to ergosterol. When it binds to that it causes the fungal membrane to become more permeable so cations like Potassium starts to leak out! This will either slow down reproduction or kill the fungus!
Is ergosterol in bacteria?
No
What is ergosterol similar to in our membranes?
Cholesterol–slightly toxic to us!
Amphotericin B is an ___ drug and many people will experience an ____ to it.
IV, infusion reaction
Describe the signs and symptoms of an amphotericin B infusion reaction.
Fever Chills Rigors (severe shaking) Nausea Headache
The signs and symptoms of amphotericin B infusion reaction is similar to red man syndrome. What is the difference?
Red man syndrome caused by histamine
Infusion reaction caused by CYTOKINES
How can we pretreat an amphotericin B infusion reaction?
Diphenhydramine (benadryl), acetaminophen (to help with fever)
How can we treat the rigors of an amphotericin B infusion reaction?
Dantrolene
Amphotericin B is very rough on the veins (i.e it causes ____). So you want to ____, watch infusions very closely, and infuse them ____.
Phlebitis
Rotate IV sites
Infuse slowly (over 2-4 hours)
Amphotericin B is very ______. Everyone will experience renal impairment with it, but this should resolve once the drug regimen is complete. What must you avoid?
Nephrotoxic
other nephrotoxic drugs (NSAIDS)
Amphotricin B patients frequently become ______. What must be monitored and why?
HYPOkalemic; potassium levels bc we don’t want a fatal arrhythemia!
Amphotericin B can cause _____ which can lead to anemia.
Bone marrow suppression
What are the 4 adverse effects of amphotericin B, other than the infusion reaction?
Phlebitis
Nephrotoxicity
HYPOkalemia
Bone marrow suppression
How can Azoles be taken?
PO
What are common azoles?
FluconAZOLE
ItraconAZOLE
How do Azoles work?
Fungi have CYP system and has an enzyme called 14-alpha-demethylase. That enzyme helps make ergosterol (which is used to make fungal cell walls strong). The azalea drugs work by inhibiting the 14-alpha-demethylase enzyme of the CYP system so ergosterol is NOT made and that means there is a WEAK, FLABBY, FUNGAL WALL
–>DIE FUNGUS
The Azoles are quite effective. One dose of fluconzole is enough to cure a typical vaginal yeast infection. A systemic infection is going to take ____ & ____. But the drugs do work well.
A lot more time and doses !
What are the adverse effects of Azoles? (3)
Decrease ejection fraction (Itraconazole)
Hepatotoxicity (both)
CYP interactions (both)
What does intraconazole do?
Decreases the ejection fraction of the heart which weakens/decreases the CONTRACTILITY. This lasts 12 hours each time a person gets a dose!!! CAN BE A REAL PROBLEM FOR PATIENTS WITH HF!!!
Both azoles can cause liver issues. Remember what??
JAUNDICE
Both azoles cause CYP interactions. They mess up the fungal cell wall CYP, but they also mess uo ours! They inhibit CYP3A4. What does that mean?
Inhibits the enzyme that chops up the drug–so the drug accumulates and increases the level of it!
This CYP interaction with Azoles is deadly for patients on anti-arrythemia drugs or drugs with a narrow therapeutic index!
Which anti fungal affects kidney?
Amp. B
Which anti fungal affects liver?
Azoles
Which drug is PO?
Azoles
