Antifungal Drugs Flashcards
Fungi
-Large and diverse group of microorganisms
-broken into yeasts and moulds
Mycoses is a
fungal infection
Fungal infections are
Normal flora of the skin, mouth, intestines, or vagina
-rise in opportunistic infections
what is part of the reason normal flora increases
broad spectrum antibiotics cause less competition
Normal flora
natural body bacteria
Fungal (mycotic) infection classifications
-superficial
-Systemic
Superficial fungal infection
-integumentary
-mucous membranes
Systemic fungal infections
-Can be life threatening
-ma require prolonged therapy
-usually occur in immunocompromised hosts
Whats the issue with systemic treatments
treatment drugs frequently prove toxic
Candida albicans
-in immunocompromised
-common yeast
-due to antibiotic therapy, antineoplastics, or immunosuppressants
Types of Candida albicans
-Oral candidiasis
-Vaginal Candidiasis
-Dermatomycoses
Oral Candidiasis
thrush of mucous membranes
Vaginal Candidisis
-Yeast infection
-Pregnancy, diabetes mellites, oral contraceptives
Dermatomycoses
-Skin (tinea/ringworm)
-Nails
-Hair
Antifungal drugs are split into
-Naturally Occurring
-Synthetic
Naturally Occuring
-Polyenes
-Echinocandins
Synthetic
-Azoles
-Pyrimidines
Polyenes
-Amphotericin B
-Nystatin
Azoles
-Fluconazole
-Miconazole
-Ketoconazole
-Itraconazole
Systemic Infections are treated with
-Amphotericin B (polyene/natural)
-Fluconazole, Ketoconazole, Itraconazole (Azoles/synthetic)
Amphotericin B (Polyene/natural) administration
-Slow IV injection
-Lipid/Non-lipid preparations
Fluconazole, Ketoconazole, Itraconazole (Azole/synthetic) administration
multiple administration routes
Superficial infections are treated with
Nystatin
Nystatin (polyene/natural) administration
-Oral infections- suspension should be swished thoroughly in the mouth as long as possible before swallowing
-Polytypical azoles
Polytypical Nystatin
-Vaginal candidiasis, skin infections (tineal)
-Fluconazole, ketoconazole, clotrimazole, miconazole
Polyenes mechanism of action (Amphotericin B + Nyststin)
-Bind to sterols in cell membrane lining
-Makes holes in cell membranes
-Fungal cell death (mostly)
What’s the danger of polyenes in high concentration
bind to cholesterol of human cells causing toxicities
Azoles mechanism of action (Fluconazole, Ketoconazole, Miconazole, Clotrimazole)
-Inhibit sterol altering enzyme (CYP 450 enzymes, ergosterol in membranes)
-lead to altered cell membrane
-Inhibit growth/kills cells
Indications of Antifungal drugs
-Systemic + Superficial infections
-Agent of choice for the treatment of severe systemic mycosis
Agent of choice for the treatment of severe systemic mycosis
-Amphotericin B
-Azoles as alternative
Amphotericin B adverse effects
Many adverse effects nontribally:
-Renal toxicity
-Impaired hepatic functions
What should to assess when administering Amphotericin B
-Kidney and liver functions
Other effects of Amphotericin B
-Fever
-Headache
-Dysrhythmias
-Malaise
-Hypotension
-Nausea + Vomiting
-Muscle +Joint pain
-Chills
-Anorexia
How to reduce the severity of infusion related reaction of Amphotericin B
Pre-treat with
-Antipyretic (acetaminophen)
-Antihistamines (diphenhydramine)
-Anti-emetics
-Use a test dose
Drug Interactions
-many azoles inhibit hepatic CYP enzymes
-Co-administration of 2-drugs that are metabolized by this system result in competition with the enzymes
-leading to higher levels of one of the drugs
