How cold-chain medicines are kept in range, and what happens when they are not

On April 2, 2025, a shipment of refrigerated injectables left a warehouse with a 48-hour delivery window. Severe thunderstorms got in the way, and the packages arrived on April 7 and 8. The products included a multivitamin injection and a generic medroxyprogesterone injection, and both appeared in FDA's enforcement report dated May 7, 2025, as Class II recalls, according to FDA enforcement records published through openFDA¹.

The recall records describe a shipping delay and cite no manufacturing defect. The question was whether the products had stayed cold enough on the way, and that could not be shown.

Temperature-controlled distribution, usually called the cold chain, covers vaccines, insulin and many injectable and biologic drugs. The rules that govern it are spread across FDA's manufacturing regulations, a 1990 rule for wholesalers, standards from the US Pharmacopeia (USP) and a federal licensing rule that is still pending. FDA's recall records show how often the system slips, and how a single warehouse problem can turn into hundreds of recall entries.

The temperature bands

A drug's label sets its storage condition (GxRadar explains how to read those lines in what the storage instructions on a medicine label mean), and that condition comes from stability testing. FDA's manufacturing rules say expiration dates must be related to the storage conditions⁶ stated on the label, as determined by stability studies, the same testing behind how expiration dates are set. Most products fall into one of a few standard bands.

Refrigerated and frozen ranges in the table come from the CDC's Vaccine Storage and Handling Toolkit², which is written for vaccine providers but reflects the bands used for most cold-chain drugs. The stability conditions are from the international Q1A(R2) guideline³ that FDA adopted as guidance in 2003. USP has noted that its room-temperature excursion limits fall within the ranges covered by the intermediate and accelerated studies in that guideline.

Room-temperature storage may get a new definition. A 2026 proposal to revise USP chapter <659>⁴ would redefine controlled room temperature as 15 to 25°C, matching the European and Japanese pharmacopeias and the World Health Organization. USP's briefing estimated that lowering the floor could cut heating and cooling energy use by 10 to 15 percent in colder climates. It would keep mean kinetic temperature, a weighted average that gives more weight to hot periods, as the tool for judging short excursions above 25°C, and USP's related chapter on mean kinetic temperature caps an allowable excursion at 24 hours.

Who has to keep it in range

Each link in the chain has its own rule. Manufacturers must have written warehousing procedures covering storage under appropriate conditions of temperature, humidity, and light⁷, under FDA's current good manufacturing practice regulations. Those same rules require a distribution system that can trace every lot so it can be recalled.

Wholesale distributors fall under minimum standards for state licensing that FDA first issued in 1990. 21 CFR 205.50⁸ requires that prescription drugs be stored at the temperatures in their labeling or in the official compendium, and at controlled room temperature if the label is silent. Distributors must use "manual, electromechanical, or electronic temperature and humidity recording equipment, devices, and/or logs" to document storage, and must quarantine drugs that are outdated, damaged, deteriorated or adulterated until they are destroyed or returned.

USP's general chapter <1079>⁵, revised in 2023 under the title "Risks and Mitigation Strategies for the Storage and Transportation of Finished Drug Products," sets out the industry's reference practices for the warehouse and the truck. It covers temperature-sensitive small molecules, vaccines, biologics and radiopharmaceuticals.

A federal licensing standard has been in the works for years. The Drug Supply Chain Security Act of 2013 directed FDA to set national licensing standards for wholesale distributors and third-party logistics providers. FDA proposed those standards on Feb. 4, 2022⁹. The proposal would require regular temperature mapping of facilities and monitoring equipment that would "immediately alert appropriate personnel of any deviations from the required storage conditions." As of early November 2026, no final rule had appeared in the Federal Register, and the statute says the wholesaler standards take effect two years after a final rule is published.

Most of the 2013 law is about tracing packages, which helps after a temperature problem by making it easier to find where a lot went. Our explainer on the Drug Supply Chain Security Act covers those requirements. FDA has exempted small dispensers¹⁰, such as independent pharmacies, from some of them until Nov. 27, 2027.

What happens after an excursion

An excursion is any time outside the labeled range. The CDC toolkit's definition is plain: "Any temperature reading outside the recommended range in the manufacturer's package insert or EUA factsheet is a temperature excursion." For vaccines, the CDC says manufacturers weigh how far out of range and for how long the product was, and that vaccines stored at inappropriate temperatures should not be administered unless the manufacturer says safety and effectiveness were not compromised.

Drugs follow a similar path. The holder documents the excursion, quarantines the product, and asks the manufacturer, which compares the time and temperature record against its stability data. If the product has already shipped onward and its condition cannot be assured, the result can be a recall.

Allowances differ by product, which is why the label matters. FDA's emergency guidance on insulin says products in the manufacturer's original vials or cartridges, opened or unopened, may be left unrefrigerated between 59°F and 86°F for up to 28 days¹¹ and continue to work, while frozen insulin should not be used. Questions about a specific medicine that arrived warm, sat in a hot car or lost refrigeration in a power outage are ones for a pharmacist or the manufacturer's line listed on the package.

What FDA's recall records show

GxRadar searched 18,076 drug recall records in openFDA, from June 2012 through Oct. 28, 2026, for reasons that cite storage or shipping temperature. We excluded records about environmental monitoring or impurity results. That left 565 records. Grouped by report date and stated reason, they trace back to about 45 separate events, because one warehouse problem can produce dozens of records, one per product.

Four events account for 470 of the 565 records, or 83 percent. Most of the records, 534, were Class II, meaning use could cause temporary or medically reversible problems. Sixteen were Class I, including a 2015 propofol recall after uncontrolled temperature excursions in transit and a 2017 lot of an intravenous fat emulsion partly exposed to subfreezing temperatures on its way to a distribution center. The 2024 group included doxycycline capsules among the generics.

The most recent case in the records is from Oct. 7, 2026, when a hormone implant was recalled after it "sat in a non-temperature-controlled" trailer "at ambient outdoor conditions for 25.5 hours." For the broader picture, see GxRadar's recall data, our explainer on how drug recalls work and our guide to checking whether a medicine was recalled. From July 30 through Oct. 28, 2026, FDA logged 212 drug recall records, 19 of them Class I, for all reasons combined.

Two dates are worth watching. USP's room-temperature change is still a proposal, and FDA's final national licensing standards, once published, would start a two-year clock for wholesale distributors. The small-dispenser exemption from tracing rules runs out on Nov. 27, 2027.