Drugs expire by rule. Devices by choice.

A drug carton missing its expiration date, packaged after September 29, 1979, is a deficiency FDA can act on by itself — no other finding required. A device carton missing one is, in most cases, exactly what the manufacturer decided to ship. The two products sit a few inches apart in the same rep’s bag, governed by two entirely different federal theories of what a date on a label is for.

The rule that applies to the drug

21 CFR 211.137 requires an expiration date on virtually every drug product, set so the product “meets applicable standards of identity, strength, quality, and purity at the time of use.” That date has to come from stability testing under 21 CFR 211.166, has to track whatever storage conditions the label states, and — for a product reconstituted before use — has to cover both the reconstituted and unreconstituted forms. The exemptions are named and narrow: homeopathic drugs, some over-the-counter products, allergenic extracts labeled “No U.S. Standard of Potency.” Nothing in 211.137 is a suggestion. An inspector who finds a non-exempt drug with no expiration date, or one not backed by the stability data 211.166 requires, has a citable deficiency before looking at anything else about the product.

The rule that doesn’t apply to the device

No device regulation reads like 211.137. FDA’s own guidance on the subject — Shelf Life of Medical Devices, issued in April 1991 and still the agency’s current word on the topic — exists to walk a manufacturer through whether a given device needs an assigned shelf life at all, what parameters determine how long it stays within specification, and what activities establish that life once the manufacturer decides one is warranted. That is a risk framework, not a mandate, and the document says so about itself in the language FDA puts on every guidance under 21 CFR 10.115: it “does not create or confer rights for or on any person and does not operate to bind FDA or the public.” A device that ships with no expiration date anywhere on its label isn’t, by itself, out of compliance with anything — it may simply be a device whose manufacturer concluded, under that 1991 framework, that none was warranted. A handful of device types have their own specific labeling regulations that do require a date; most don’t, and the default is a manufacturer decision, not a federal one.

A drug’s expiration date answers a question FDA requires an answer to. A device’s, where one exists at all, answers a question the manufacturer decided was worth answering.

The one rule that reaches every device anyway

There is a federal rule that touches a device’s date — it just isn’t about whether the date should exist. 21 CFR 801.18, added by the Unique Device Identification System final rule (78 FR 58785, Sept. 24, 2013), governs the format of any printed expiration date, manufacture date, or other date meant for the device user: year first, four digits; month and day, two digits each; hyphens between them. FDA’s own example in the rule is January 2, 2014, written as 2014-01-02. The narrow exceptions are a combination product properly bearing an NDC number, and an electronic product whose date format is set instead by the radiological health standard at 21 CFR 1010.3(a)(2)(ii). Put plainly: 801.18 never asks whether a device needed a shelf life study behind that date. It only governs how the date reads once the manufacturer, for its own reasons, put one on.

The practice

A date on a device label, read on its own, answers neither of the two questions a reader usually assumes it answers. It doesn’t say the manufacturer ran the shelf-life work FDA’s 1991 guidance describes — that guidance doesn’t require the work, and the date’s presence alone doesn’t prove it happened. And it doesn’t say anything about safety or performance at all — 801.18 would be satisfied by a correctly formatted date on a device that should never have shipped. A missing expiration date on a device file, in a recall narrative, or in a competitor’s labeling is not automatically a gap the way the same absence would be on a drug; reading it as one, in either direction, is a mistake this asymmetry makes easy to make. This is regulatory intelligence and method, never regulatory advice about whether a specific device needs an assigned shelf life, or whether a specific label’s dating already satisfies 801.18 — those are determinations for your regulatory professional, against the device’s own file.