21 CFR 201.66 explained
21 CFR 201.66 is the section of the US Code of Federal Regulations that standardizes the OTC "Drug Facts" labeling. It was finalized by the FDA to give over-the-counter drug labels a single, predictable format — the same reason nutrition labels look alike across food products.
The rule does two things. First, it sets the content: which headings must appear, what each must contain, and the order they appear in. Second, it sets the graphic requirements: the headings must be bold, the panel must be enclosed in a bounding box (or barbell rules), the sections must be separated by rules of graded thickness, and the type must meet a minimum size so the panel stays legible.
The graphic requirements are specific. The title "Drug Facts" is the largest, boldest text. A heavy "barbell" bar sits under the title. Top-level headings are separated by medium-weight horizontal rules, and sub-parts within a section are separated by hairline rules. Body text has a minimum type size (generally 6 point), and everything is printed in a high-contrast color combination — black on white is standard.
The regulation also allows a horizontal (side-by-side) layout for small packages and a "Drug Facts (continued)" continuation when the panel does not fit in one column, so the same structure carries across multiple panels or pages.
Drug Facts Panel Maker lays out your content in the 21 CFR 201.66 format. It is a drafting aid, not regulatory, legal, or medical advice, and does not verify that your dosing, uses, warnings, or claims are correct. Verify every panel with a qualified regulatory person before compliance use.
Build a Drug Facts panel — free draft
What 21 CFR 201.66 requires at a glance
- A fixed set of headings in a fixed order.
- The title "Drug Facts" in the largest, boldest type.
- A bounding box or barbell rules around the whole panel.
- Graded horizontal rules: a heavy bar under the title, medium rules between headings, hairlines between sub-parts.
- Bold headings that span the full width of the panel.
- A minimum type size (generally 6 point) for legibility.
- High-contrast printing — black text on a white background is standard.
- A "Drug Facts (continued)" title when the content overflows.
Questions
Does 21 CFR 201.66 apply to supplements?
No. Dietary supplements use a "Supplement Facts" panel under a different regulation (21 CFR 101.36). The Drug Facts panel applies to products marketed as OTC drugs. A product's classification depends on its ingredients and claims — verify with a regulatory professional.
What is the minimum type size?
The regulation sets a minimum type size (generally 6 point for most panel text, with larger minimums for the title and headings) and minimum leading, so the panel stays readable. Drug Facts Panel Maker enforces a 6 point floor on every line it draws.
Is black-on-white required?
The rule requires high contrast. Black text on a white or other light, contrasting background is the standard and safest choice, and it is what this tool renders.