Final answer:
The drug of choice for esophageal candidiasis is generally the antifungal medication fluconazole, used systemically. Itraconazole may be considered for fluconazole-resistant strains, while Amphotericin B is used for severe or azole-resistant cases.
Step-by-step explanation:
The drug of choice (DOC) for esophageal candidiasis is an antifungal medication. The systemic azole antifungal fluconazole is commonly used and can be administered orally or intravenously. It works by inhibiting ergosterol biosynthesis, which is essential for fungal cell membrane integrity. For fluconazole-resistant strains, systemic itraconazole may be considered. In severe cases or when the infection is caused by an azole-resistant strain of Candida, Amphotericin B may be employed. This broad-spectrum antifungal disturbs the fungal cell membrane, but it can also produce side effects, making careful monitoring by clinicians essential.
It is important to note that these treatments are typically more selective and come with fewer side effects compared to some of the older antifungals. In patients with compromised immune systems, like those with HIV/AIDS, who are more prone to esophageal candidiasis, long-term suppressive therapy may be necessary to control the infection.