Oral Antifungals

Azoles

• Examples:
  • Fluconazole (e.g., Diflucan)
  • Itraconazole (e.g., Sporanox)
• PBS indications
  • Fluconazole:
    • Treatment of systemic candidiasis and cryptococcal infections, including meningitis.
    • Prevention of fungal infections in immunocompromised patients.
  • Itraconazole:
    • Treatment of systemic mycoses, such as aspergillosis, blastomycosis, histoplasmosis, and others.
    • Certain chronic fungal infections of the nails, skin, or mucous membranes when other treatments are inappropriate or have failed.
• Side Effects:
  • Gastrointestinal disturbances (nausea, vomiting, abdominal pain)
  • Headaches, dizziness
  • Rash
  • Elevated liver enzymes, hepatotoxicity (rare but serious)
  • Cardiac failure (rare, with itraconazole)

2. Terbinafine

• Example:
  • Terbinafine (e.g., Lamisil)
• Terbinafine PBS indications
  • Treatment of fungal skin infections and onychomycosis (nail fungus) where topical therapy has failed or is inappropriate.
  • Particularly useful in cases of dermatophyte (tinea) infections.
• Side Effects:
  • Gastrointestinal upset (diarrhea, dyspepsia)
  • Headache
  • Rash, urticaria
  • Changes in taste or loss of taste, which is usually reversible
  • Elevated liver enzymes, hepatotoxicity (less common but can be serious)
  • Blood dyscrasias (rare)

3. Griseofulvin

• Griseofulvin (e.g., Grifulvin V, Gris-PEG)
• PBS indications
  • Treatment of dermatophyte infections of the skin, hair, and nails where topical therapy is inappropriate or has failed.
  • Often used in cases where the fungal infection is extensive, deep, or difficult to treat with topical agents alone.
• Side Effects:
  • Gastrointestinal discomfort
  • Headaches
  • Photosensitivity
  • Hepatotoxicity
  • Blood dyscrasias
  • Teratogenic effects (not recommended during pregnancy)

Monitoring and Considerations

• Liver Function: Since many oral antifungals can affect liver function, liver enzymes should be monitored before and during treatment, especially in patients with pre-existing liver conditions or those taking other hepatotoxic drugs.
• Kidney Function: Monitoring may be required, especially in patients with renal impairment.
• Drug Interactions: Oral antifungals can interact with a variety of other medications. For example, they can increase the concentration of certain drugs like warfarin, leading to an increased risk of bleeding.
• Allergic Reactions: Although rare, severe allergic reactions can occur.
• Pregnancy and Breastfeeding: Some antifungals are contraindicated during pregnancy and breastfeeding.