Antifungal Drugs: Classification, Mechanism, Uses & Side Effects

📌 Introduction  

Antifungal drugs are an important group of antimicrobial agents used to treat fungal infections. Fungal infections range from superficial infections like skin and nail infections to serious systemic infections affecting internal organs.  

With increasing use of antibiotics and immunosuppressive drugs, fungal infections are becoming more common. Therefore, antifungal drugs are frequently asked in GPAT, DSSSB, and other pharmacy exams.

🔍 What are Fungal Infections?  

Fungal infections (mycoses) are caused by fungi such as Candida, Aspergillus, and Dermatophytes.  

They are classified as:  

• Superficial infections → skin, hair, nails  

• Systemic infections → lungs, blood, organs  

📝 Classification of Antifungal Drugs  

Antifungal drugs are classified based on their mechanism of action:

• Polyenes  

Examples: Amphotericin B, Nystatin  

• Azoles  

Examples: Fluconazole, Ketoconazole, Itraconazole  

• Echinocandins  

Examples: Caspofungin  

• Allylamines  

Examples: Terbinafine  

• Antimetabolites  

Example: Flucytosine  

🧬 Mechanism of Action  

Antifungal drugs mainly act on fungal cell membrane or cell wall:

• Polyenes → bind to ergosterol → create pores → cell death  

• Azoles → inhibit ergosterol synthesis  

• Echinocandins → inhibit cell wall synthesis  

• Allylamines → inhibit squalene epoxidase  

• Flucytosine → inhibit DNA/RNA synthesis  

🩺 Pharmacological Effects  

• Destroy fungal cells  

• Stop fungal growth  

• Treat superficial and systemic infections  

💊 Therapeutic Uses  

Antifungal drugs are used in:

• Skin infections (ringworm, athlete’s foot)  

• Candidiasis  

• Aspergillosis  

• Systemic fungal infections  

• Nail infections  

🚨 Side Effects  

• Nausea, vomiting  

• Liver toxicity (azoles)  

• Kidney toxicity (Amphotericin B)  

• Skin rash  

• Headache  

📑 Important Exam Points  

• Amphotericin B → most potent antifungal  

• Fluconazole → widely used azole  

• Terbinafine → for skin infections  

• Flucytosine → antimetabolite  

📍 Contraindications & Precautions  

• Liver disease (use azoles carefully)  

• Kidney problems (Amphotericin B caution)  

• Pregnancy (some antifungals contraindicated)  

🎯 Conclusion  

Antifungal drugs are essential for treating a wide range of fungal infections. Understanding their classification, mechanism, uses, and side effects is crucial for exams and clinical practice. Regular revision and MCQs will help in mastering this topic.

👉 Practice MCQs in evening post