Some antifungal medications work by blocking dna synthesis in the fungal cell. During which phase of the cell cycle do these medications work?

The anti-fungal drugs kills the fungus and treats the disease by blocking the DNA synthesis in the cell of the infecting fungi. During the S phase of the interphase, the DNA synthesis occurs. By blocking this phase of the cell cycle, the anti-fungal drugs ensures that the fungi cells do not replicate. The synthesis phase is blocked.

Hence, the answer is 'S-phase'.