Type sizes
On this page11
The title
"Drug Facts" "shall appear in a type size larger than the largest type size used in the Drug Facts labeling". So it scales with your panel rather than sitting at a fixed size.
The headings
"The larger of either 8-point or greater type, or 2-point sizes greater than the point size of the text". Which means setting the body larger pushes the headings up too.
The content
"No smaller than 6-point type" for everything else. That is the floor and it is the number to measure your label area against.
Six point is small
And it is still a real amount of space once you have the identity, the indication, five warnings, the directions and the inactive ingredients in a structured panel with rules and headings.
The panel has a structure, not just a size
Headings in a set order, bullets, barlines and an enclosing box. The format is part of the requirement and it costs area beyond the words themselves.
Which is why it has to be laid out to be measured
A word count does not tell you whether a panel fits. A typeset panel at 6-point with its box and barlines does, and it takes an afternoon.
Then measure your container
Label area is a measurable property of a bottle: the printable height and the circumference you can wrap without the label lifting. Get it from the drawing rather than estimating.
Cylindrical containers are the easy case
A straight wall takes a wrap label and the whole circumference is usable. A tapered bottle, a cosmo oval or a jar with a shoulder gives you much less than its size suggests.
Which is an argument for the packer bottle
81 PET packers and 46 HDPE packers on this shelf. Straight wall, wide shoulder, generous label panel, and the format most able to carry a Drug Facts panel at a usable size.
And against the double wall jar
22 round base and 15 straight base double wall jars. They look expensive and they give you an outer wall to label and a volume penalty. Fine for a cosmetic mask, awkward for a drug.