By the PharmaTradz BD Team. Published October 2026.
The cold chain is the unbroken series of temperature-controlled storage and transport steps that keeps a temperature-sensitive medicine within its approved range from the factory to the patient. Vaccines, insulins, most biologics and many other injectables lose potency, sometimes irreversibly and invisibly, if they get too warm or freeze. A medicine that has been out of range may look exactly the same, which is why the cold chain depends on qualified equipment, continuous monitoring and records rather than on inspecting the product at the end.
The temperature ranges you will meet
| Label condition | Typical range | Examples |
|---|---|---|
| Refrigerated | 2 to 8 °C | Most vaccines, insulins, monoclonal antibodies, many biologics |
| Frozen | Typically -25 to -15 °C | Some vaccines and biological materials |
| Ultra-cold | -60 °C or colder | Some mRNA vaccines and cell and gene therapies (some much colder, in liquid nitrogen vapour) |
| Controlled room temperature | Defined in each market, typically up to 25 °C | Many tablets and capsules; not cold chain, but still temperature-controlled |
The exact limits, and whether short excursions are allowed, come from each product's approved labelling and stability data, not from a general rule. Freezing is often as damaging as overheating: many vaccines and protein products must never freeze.
What makes a cold chain work
Qualified storage. Pharmaceutical refrigerators, freezers and cold rooms that have been temperature-mapped, so you know every shelf stays in range, with alarms and backup power.
Qualified packaging and transport. Either passive shippers, insulated boxes with conditioned gel packs or phase-change materials designed to hold a range for a set number of hours, or active containers with their own powered cooling. Each solution should be qualified for the route and season it is used on.
Continuous monitoring. Data loggers travel with the shipment and record the temperature throughout, so the receiver can see the whole journey. Many vaccines also carry vaccine vial monitors, labels that change colour with cumulative heat exposure.
Procedures and people. Good Distribution Practice rules require written procedures for packing, receiving, handling excursions and recalls, and staff trained to follow them. Most cold-chain failures happen at hand-over points: at the airport, at customs or on the last mile, not inside the cold room.
When something goes wrong: excursions
A temperature excursion is any time the product leaves its approved range. It does not automatically mean the product must be destroyed, but it must be investigated. The receiver quarantines the goods, downloads the logger data and asks the manufacturer, who holds the stability data, whether the product can still be used. Decisions should be documented, and if the cause was a packing or route problem, it should be fixed for next time.
Cold chain in hot climates and remote areas
The hardest cold chains are often in the markets that need them most. High ambient temperatures put more strain on shippers and storage, power cuts can threaten refrigerators, and the last stretch from a regional store to a clinic may be long and slow. Programmes in these settings rely on equipment designed for them, such as solar-powered refrigerators and long-hold cold boxes, many of them assessed under WHO's performance, quality and safety (PQS) scheme, together with careful planning of stock levels so that products are not held longer than necessary. For importers, it means choosing shippers qualified for summer profiles on your route, planning arrivals around customs working hours, and having a clear plan for storage at every hand-over.
What importers and buyers should plan for
Agree in writing who is responsible at each stage: packing at the factory, freight, customs clearance and delivery to your warehouse. The Incoterm you choose sets where risk passes, but cold chain responsibility needs its own clear agreement.
Choose routes and timings that avoid weekend arrivals and long customs holds, and make sure your clearing agent can move cold-chain goods quickly.
Ask for the shipper qualification data and confirm the duration it covers is longer than your door-to-door transit time, with a margin.
Check your own storage capacity and its qualification before the goods arrive, including backup power. Our guide to starting a pharmaceutical import business covers the licences and premises side.
And remember why it matters: most products that need a cold chain are biologics, which our explainer on small molecules versus biologics explains.
How PharmaTradz can help
Our cold-chain logistics service helps buyers plan temperature-controlled shipments from manufacturers to their markets, including packaging, monitoring and documentation. Tell us the product, its storage condition, quantity and destination, and send us an RFQ. For other terms, see our pharma abbreviations A-Z.
Frequently Asked Questions(FAQs)
What is the cold chain in pharma?
The unbroken series of temperature-controlled storage and transport steps that keeps a temperature-sensitive medicine within its approved range from manufacture to the patient.
What temperature is the pharmaceutical cold chain?
Most cold-chain medicines are stored refrigerated at 2 to 8 °C. Some are frozen, typically -25 to -15 °C, and some vaccines and cell and gene therapies need -60 °C or colder. Each product's labelling sets its exact range.
Which medicines need a cold chain?
Most vaccines, insulins, monoclonal antibodies and other biologics, as well as some other injectables and eye drops. Many must also never be frozen.
What is a temperature excursion?
Any period when a product leaves its approved temperature range. The goods are quarantined and the logger data is reviewed with the manufacturer, who decides from its stability data whether the product can still be used.
What is the difference between passive and active cold-chain packaging?
Passive shippers use insulation and pre-conditioned coolants to hold a range for a set time. Active containers have their own powered cooling and temperature control, usually for larger or longer shipments.
