Answer:
Fungi are basically eukaryotes in nature just as the human cells are eukaryotic in nature. This attributes makes it uneasy to target only the fungus.
The use of Antibiotics have shown to have an impact on the peptidoglycan layer in bacteria, the peptidoglycan structure is absent in humans resulting in little or no risk of injury or damage.
As stated earlier on that the structure and cellular processes in the human cells and fungal cells are more similar, treatment have a higher chance of endangering the human cells.