Antifungal Drugs

Introduction & importance

• Fungi are eukaryotes, so selectively killing the pathogen without harming the human host is inherently hard — the few exploitable targets are membrane ergosterol, the fungal capacity to deaminate cytosine, and the β-glucan / chitin cell wall.
• The burden of invasive (life-threatening) mycoses has risen sharply with the expanding immunocompromised population — transplant recipients, cancer chemotherapy, immunosuppressants, indwelling devices and HIV/AIDS; much of it is iatrogenic (broad-spectrum antibiotics, corticosteroids, anticancer drugs break down host defences). Mortality of invasive disease remains high.
• Therapeutically the antifungals split into (a) systemic drugs for deep invasive mycoses, (b) oral drugs for mucocutaneous infection, and (c) topical drugs for superficial infection.
• Scope note: the polyene prototype amphotericin B is covered in its own dedicated topic and appears here only as the comparator/anchor for spectrum, toxicity and combination regimens.