CFR › Title 21 › Part 335Part 335 — Antidiarrheal Drug Products for Over-the-Counter Human UseSubpart A — General Provisions§ 335.1— Scope.§ 335.3— Definitions.Subpart B — Active Ingredients§ 335.10— Antidiarrheal active ingredients.Subpart C — Labeling§ 335.50— Labeling of antidiarrheal drug products.