While not the most popular ingredient, mold is indeed used for producing multiple drugs. All of these drugs belong to the penicillin family.
The most known drug from this family, of course, penicillin. There are also drugs like amoxicillin and ampicillin.
Why is mold used for producing these drugs?
Certain mold species kill certain bacteria. This is why some people started researching how to grow these molds and how to effectively produce drugs out of them.