Cancer Medication Abroad: Cold Chains, Customs, Counterfeit Risk

Counterfeit durvalumab with zero active ingredient reached patients in 2025. Here is what oncology travellers must know about customs, cold chains, and why local sourcing is the biggest risk.

Travelling with cancer medication: the risks no one talks about

In January 2025, the WHO issued an alert confirming that counterfeit vials of durvalumab (Imfinzi) containing no active ingredient had been identified in Armenia, Lebanon, and Turkey. For oncology travellers, this is the sharpest possible warning: the medication you source outside your normal supply chain may contain nothing at all.

This article covers the three issues that matter most for cancer and chemotherapy travellers: how to carry your medication safely through security and customs, how to protect temperature-sensitive drugs, and why attempting to source or refill locally carries risks that go beyond inconvenience.

Medical disclaimer: This article is for informational purposes only and does not constitute medical advice. Cancer treatment regimens are highly individual. Always consult your oncologist before travelling, and never adjust your treatment schedule or source of medication without specialist guidance.

The counterfeit supply chain problem

Oncology drugs are among the most counterfeited pharmaceuticals in the world. A 2025 investigation found that nearly 20% of cancer drugs tested in Ethiopia, Kenya, Malawi, and Cameroon were defective, containing incorrect levels of active ingredients. The problem extends well beyond low-income settings.^[1]

In June 2026, Mexican federal authorities seized vials labelled as Keytruda (pembrolizumab) from a counterfeit ring outside Mexico City. It was the second such operation in Mexico involving that brand label. These were not remote or unusual incidents.^[2]

The practical consequence for you as a traveller is straightforward: bring your entire treatment supply from your verified home pharmacy. Do not attempt to refill, supplement, or source any oncology medication locally, even from a pharmacy that looks legitimate.

Getting through security with cancer medication

The TSA (which governs airport security screening at US departure points) allows passengers to bring medically necessary liquids in excess of 100 ml in carry-on baggage. This exemption covers liquid cancer medications, pre-filled syringes, and the ice packs needed to keep them cold. You must declare these items to the security officer before screening begins.^[3] Rules for flying with liquid medication are explained in detail in our dedicated guide.

Equivalent exemptions apply at airports governed by other national security agencies, including those in EU member states and the UK, but the specific declaration process varies. Check the security agency for your departure airport, not a general airline policy.

Three documents to carry at every checkpoint:

An oncologist's letter listing each medication by its generic name, the dose, and the medical necessity for travel.
The original pharmacy-labelled packaging, showing your name, the drug name, the prescriber, and the dispensing date.
A copy of your full medication list stored digitally, ideally within a structured record such as your International Patient Summary.

Customs rules by destination: what you must check

Airport security and customs are entirely separate processes. Security checks what you carry onto the aircraft. Customs, at your destination, governs whether you may legally bring that medication into the country at all.

Japan, for example, requires a Yunyu Kakunin-sho (import confirmation) if you need more than a one-month supply of a prescription medicine. Chemotherapy courses often require several months of medication, which means prior approval through Japan's MHLW online system before you travel.^[4] See our guide on Japan medication rules for more information on import requirements.

The FDA generally allows a personal supply of up to 90 days for a serious condition such as cancer when the drug is not available domestically or is part of ongoing treatment begun abroad. This applies to medication entering the US, not to what you carry out.^[5]

Some oncology drugs fall under controlled-substance schedules. Opioid pain medications used alongside cancer treatment are regulated by the International Narcotics Control Board's Yellow List and by national narcotics laws in every country you transit through. Declaring them and carrying original pharmacy labelling is non-negotiable.

If any drug on your regimen appears on a controlled substance schedule, contact the destination country's drug regulator or embassy at least eight weeks before departure. Some countries require import permits that cannot be obtained on arrival.

Cold-chain protection from door to door

Cargo hold temperatures on commercial aircraft can swing well below freezing at altitude and dangerously warm during ground delays. Any oncology drug that requires refrigeration must travel in the cabin with you, not in checked luggage.

Most cancer biologics and targeted therapies require storage between 2°C and 8°C. A validated insulated travel case with biogel packs that freeze above 0°C (to prevent accidental freezing of the drug) is the practical standard. Keep the case under the seat in front of you, not in the overhead locker, where temperature and access are less reliable. For more practical cold chain advice, see our guide on how to travel with insulin, biologics and refrigerated medication.

Do not assume the aircraft has a passenger-accessible refrigerator. Some long-haul flight attendants will store medication in a galley unit if asked, but this is an exception and cannot be guaranteed. Your cold chain is your responsibility from the moment you leave home.

For long journeys with layovers, consider splitting your supply. Keep enough for the flight and first 48 hours in your carry-on; pack the remainder in a labelled, insulated case in checked luggage as a secondary backup. If the checked bag is delayed, you are not immediately without medication.

Why you cannot rely on sourcing medication at your destination

The temptation to top up a supply locally is understandable, particularly on longer trips. The risk is not simply regulatory.

The WHO estimates that in some regions more than 30% of medicines on sale can be counterfeit. Oncology drugs are particularly targeted because they command high prices and patients are often desperate. A vial that looks identical to your regular brand may contain saline, an incorrect dose, or degraded active ingredient.^[7]

The cold chain issue compounds this risk. A locally sourced biologic that has been improperly stored at any point in its distribution journey may have lost potency. You will not know from appearance alone.

The only reliable strategy is to bring your entire supply from a verified source. If your trip requires more medication than customs limits allow in a single entry, plan your itinerary to align supply with entry points, or obtain advance import approval from the destination country's drug regulator.

Building a pre-travel documentation pack

A well-prepared documentation pack can resolve most customs questions in minutes. Assemble it at least four weeks before departure, not the night before.

Oncologist's letter. On headed paper, signed, listing every drug by generic and brand name, dose, frequency, and the medical necessity. Request an English translation if your destination country uses a different official language.

Original pharmacy receipts and dispensing records. These establish provenance and demonstrate the drugs came from a regulated supply chain.

Destination regulator approval. If your destination country requires an import permit for any drug in your pack, obtain it before you travel. Japan's MHLW, for example, moved its import confirmation process fully online in July 2025.

Digital record. Upload your medication list, diagnoses, allergies, and treatment summary to a structured format such as an International Patient Summary (IPS). This makes your records readable by emergency clinicians anywhere, without the risk of losing a paper letter. Nomedic stores your records in the IPS format and lets you share them instantly. Check the medication import rules glossary for country-specific reference.

If something goes wrong mid-trip

Lost luggage, theft, or a temperature excursion that renders a biologic unusable are all realistic scenarios. Having a plan before they happen is the difference between a treatment disruption and a crisis.

Contact your oncology team at home as the first step, not a local pharmacy. They can advise on whether a missed dose is clinically significant, whether an alternative formulation exists, and whether emergency authorisation for a local supply is feasible. Most hospital oncology units have out-of-hours contact numbers specifically for patients abroad.

Ensure your travel insurance policy covers oncology-related emergencies explicitly. Standard policies often exclude pre-existing conditions unless declared and accepted at policy inception. Verify cover before departure, not during a crisis.

Frequently asked questions

Is it legal to bring chemotherapy medication through customs?

Chemotherapy and other prescription cancer medications are legal to carry across borders for personal use, provided you have a valid prescription, an oncologist's letter, and original packaging. Individual countries set their own quantity limits and, for certain drugs classified under narcotics schedules, may require an advance import permit. Check the drug regulator of your specific destination before travel.

Can I carry cancer medication in my hand luggage on a plane?

Yes. The TSA exempts medically necessary liquids from the standard 100 ml carry-on liquid limit, and equivalent exemptions apply at airports in EU member states and the UK. You must declare liquid medications to the security officer before screening. Solid-form medications have no quantity cap at the checkpoint.

How do I keep biologic cancer medication cold on a long-haul flight?

Use a validated insulated travel case with biogel packs that freeze above 0°C, to prevent the medication freezing. Keep the case in the cabin, under the seat in front of you. Cargo hold temperatures are unsafe for refrigerated drugs. Do not rely on the aircraft having a passenger-accessible refrigerator.

How much cancer medication can I bring into Japan?

Japan's MHLW allows a personal import of up to one month's supply of a prescription medication without advance approval. Quantities above that require a Yunyu Kakunin-sho (import confirmation), which must be obtained through MHLW's online system before you arrive. Since July 2025, online application is the standard method.

What happens if I run out of chemotherapy medication abroad?

Contact your oncology team at home first. They can advise on clinical risk and whether emergency authorisation for a local supply is feasible. Do not attempt to source oncology drugs from a local pharmacy independently, given documented counterfeit risks in multiple countries.

Are counterfeit cancer drugs a real risk in popular travel destinations?

Yes. WHO issued an alert in January 2025 confirming counterfeit durvalumab (Imfinzi) containing no active ingredient had been found in Turkey and Armenia. In June 2026, vials bearing Keytruda labels were seized from a counterfeit ring in Mexico. These are not isolated incidents, and the counterfeit oncology drug trade is documented across multiple continents.