Fungal Infections and malaria Flashcards
Is Fluconazole or Itraconazole more readily absorbed?
Fluconazole
What is amphotericin B used for?
Aspergillosis, blastomycosis, candidiasis, cryptococcosis
Does amphotericin B need to be prescribed by brand?
Yes
Name 7 antifungal drugs?
Fluconazole Ketoconazole Itraconazole Amphotericin B Nystatin Voriconazole Miconazole
What is the mechanism of action of antifungal drugs?
Fungal cells contain ergosterol (not found in human/animal cells), antifungals bind to ergosterol creating pores as well as inhibiting ergosterol synthesis.
What are the main side effects of fluconazole? (3)
1) Prolonged QT interval
2) Hepatotoxicity
3) Renal impairment
What patient groups should avoid fluconazole? (2)
1) liver disease
2) pregnancy (teratogenic)
Which antifungal’s are CYP450 inhibitors?
Fluconazole
Ketoconazole
Itraconazole
What drugs do antifungals interact with?
1) CYP450 substrates
2) QT prolonging drugs e.g amiodarone, antipsychotics, quinolones etc
What are the main side effects of Voriconazole?
Hepatotoxicity
Photosensitivity (check for malignancy and seek medical attention if sunburnt)
What must you carry if you are taking voriconazole?
An alert card
What is nystatin normally used for? what are the typical dosage instructions?
Oral thrush-100,000 units QD for 7 days
What age group can fluconazole 150mg be sold to the public OTC?
16-60 for candidiasis
What must you monitor in patients taking LT treatment of fluconazole?
Liver enzymes before and during treatment
What must you monitor when taking LT treatment of voriconazole?
Renal and hepatic function before starting and then at least weekly for one month and then monthly.
Check for malignancy and avoid sunlight.
Hepatotoxicity is also associated with another antifungal, please name it?
Ketoconazole
What are the general monitoring requirements for antifungals?
1) ECG
2) Adrenal function (can cause adrenal insufficiency)
3) Hepatic function
What is the most common cause of fungal meningitis?
Cryptococcal meningitis
Can you use Itraconazole in heart failure or history of heart failure?
AVOID
How would you treat fungal meningitis?
IV amphotericin followed by oral fluconazole
What are the 1st and 2nd line treatments for aspergillosis?
1) Voriconazole
2) Liposomal amphotericin (alternatives are itraconazole or caspofungin)
What is tinea capitis?
Fungal infection of the scalp