Antifungals Flashcards
Fungal Infections are called..
Mycoses
Causes of fungal infections
Normal flora of skin, mouth, intestines, vagina
-Rise in opportunistic infections
-Broad-spectrum antibiotics
Mycotic (fungal) infection classifications
superficial:Integumentary, mucous membranes
Systemic: Can be life threatening, require prolonged drug therapy, Usually occurs in immunocompromised host
Common yeast infection in immunocompromised patients
Candida Albicans
Due to antibacterial therapy, atineoplastics, immunosuppressants
What are natural and synthetic antifungals called?
Naturally occurring: Polyenes
Synthetic: Azoles
What are examples of a polyene (natural) antifungal drug?
Amphotericin B
Nystatin
What are examples of Azoles (synthetic) antifungal drugs?
Ketocanazole
Which anti-fungal drugs are given for systemic infections?
Amphotericin B SLOW IV (Polyene-naturally occuring)
Ketoconazole (Azole - synthetic). Multiple routes of admin
Which antifungal drugs are given for superficial infections
Nystatin (Polyene): Swish suspension in mouth before swallowing for oral infection
Ketoconazole (Azole)
Polyenes (amphotericin B and Nystatin) mechanism of action
Bind to sterols in cell membrane
Makes holes in fungi cell membrane
Causes fungal fell death
High concentration bind to cholesterol of human cell causing toxicities
Azoles (Ketoconazole) mechanism of action
Inhibits sterol-altering enzyme (CYP450 enzymes, less ergosterol in membranes)
Leads to altered cell membrane
Inhibits growth, thus killing cells
What is the anti-fungal of choice for the treatment of severe systemic mycoses?
Amphotericin B
Main concerns with adverse Effects of Amphotericin B
Main concerns:
•Renal toxicity (K+ loss)
•Impaired hepatic functions
Assess kidney and liver functions before systemic administration
To reduce severity of infusion-related reactions of Amphotericin B, pretreat with:
•Antipyretic (acetaminophen)
•Antihistamines (diphenhydramine)
•Anti-emetics
Many azoles inhibit..
Hepatic CYP enzymes
Administration of 2 drugs that are metabolized by this system may result in competition for these enzymes (higher levels or one of the drugs)
