Visiting the UK when you use a cannabis-based medicine at home.

Can I bring my own medical marijuana or medicinal cannabis to the UK?

Sometimes, but often not. The Home Office lets visitors carry up to three months' supply of some controlled medicines without a licence. The medicine must have been lawfully prescribed and dispensed to you in the country where you normally live.

Cannabis-based medicines have an extra rule, which the UK has given the International Narcotics Control Board. You may only carry one if a clinician prescribed it to you. It must also meet the UK's legal definition of a "cannabis-based product for medicinal use in humans". You should carry a clinician's letter that explains how it meets that definition. Cannabis that doesn't meet it can't be brought in without a Home Office licence. And controlled medicines posted to you from overseas will be seized.

The UK's rules are only part of it. Your own country's law on leaving applies too, and so does the law of every country where you change planes. US Customs and Border Protection, for example, says federal law bans taking marijuana out of the United States. If you're unsure, ask the Home Office's Drug and Firearms Licensing Unit before you travel. (Checked 17 October 2026.)

What the UK's own rules say

You must carry the medicine yourself, in your hand luggage. It can be taken away at the border if you can't prove it was prescribed for you. Carry a letter from your prescriber that gives:

• Your name and your travel dates.
• Each medicine, with how much you're carrying, its dose and its strength.
• The prescriber's signature and professional registration details.

The legal definition is about the product. It has to be produced for medicinal use in humans, and it has to be a medicinal product. Cannabis that doesn't meet the definition stays in Schedule 1, the most restricted group. For travellers, the UK says it will ordinarily only issue a Schedule 1 licence when the drug is prescribed as part of a clinical trial.

If you think your medicine might qualify, email the Drug and Firearms Licensing Unit before you travel, at dflu.ie@homeoffice.gov.uk. And don't post medicine to yourself in the UK.

If you live in the United States

Under US federal law, marijuana has long been a controlled substance, whatever your state allows. US Customs and Border Protection's guidance says federal law bans taking marijuana into or out of the country, whether it's medical or recreational. It says doing so may lead to seizure, fines or arrest. When I checked that guidance in October 2026, it hadn't changed since 2023.

Something did change in 2026. A federal order in April 2026 moved two things into Schedule III: marijuana covered by a state medical marijuana licence, and FDA approved products. That order is being challenged in the US courts. The same rule added them to the list of substances that need a federal permit to import or export. The TSA's website now lists medical marijuana as allowed through airport security with "special instructions". But airport security and customs are separate things. At the border, it's CBP that enforces federal law.

On the UK side, the Home Office's rules are written for medicines prescribed to you by a clinician. They don't mention US state medical cards or certifications. Nor do they say whether a product bought with one would count. The US State Department's advice for travellers to the UK is to confirm your medicine is legal here. It notes that UK law bans some drugs that are legal in some US states.

My reading is that there's no clear, official route for an American to carry medical marijuana to the UK at the moment. If it goes wrong, the consequences fall on you.

If you live in Australia

When you leave Australia, the Office of Drug Control says you must follow the rules of the country you're entering. It warns that some countries have very strict rules on medicinal cannabis. It also says it can't advise on each country's rules.

The bigger issue is the journey. Many routes from Australia to the UK change planes on the way. The law of every country you land in applies to you, even if you never leave the airport. Smartraveller, the Australian Government's travel advice service, says not to bring medicinal cannabis to Singapore, even in transit. It says the United Arab Emirates has a zero tolerance policy on drugs that includes travellers passing through. It also warns that flights in the Middle East can be diverted with little or no notice. A diversion or an emergency landing could put you on the ground in a country with strict drug laws. Paperwork from home doesn't change that country's law.

If you live somewhere else

Check your own country's rules for leaving with your medicine and for bringing it back. Check the rules of any country you'll pass through, too. Two examples. Canada says it's illegal to take medical cannabis across its border in either direction without authorisation from Health Canada. It says individual exemptions are issued only in rare and exceptional circumstances. Ireland says prescribed cannabis-based products aren't permitted to be brought into Ireland. The International Narcotics Control Board keeps a list of each country's rules for travellers with controlled medicines. It's a good place to start.

Can a visitor be prescribed a cannabis-based medicine in the UK?

UK law sets out who can prescribe, not where the patient lives. Since 1 November 2018, an unlicensed cannabis-based medicine can only be prescribed by a doctor on the General Medical Council's Specialist Register. Northern Ireland made the same change under its own regulations on the same day. Most cannabis-based medicines prescribed in the UK are unlicensed.

Whether to prescribe for anyone, visitor or resident, is that doctor's decision. Many people aren't suitable, and there's no guarantee of a prescription. Nearly all prescribing is private, so you pay for consultations and for the medicine itself. Not every UK clinic sees visitors. If you do contact a clinic, you can check it's registered with the regulator. That's the Care Quality Commission in England, Healthcare Improvement Scotland, Healthcare Inspectorate Wales, or the RQIA in Northern Ireland.

Two rules often surprise visitors. One is that a UK pharmacy can't dispense this kind of controlled drug on a prescription written abroad. That's because the law requires the prescriber's address to be in the UK. The other is that the NHS rarely prescribes cannabis-based medicines for anyone. So being able to use the NHS doesn't change much here.

What would a UK clinic ask for?

Mostly evidence about your health. Each clinic sets its own process, but clinics usually ask for:

• Medical records showing your diagnosis and the treatments you've already tried. This is the part that matters most. GMC guidance says doctors must not prescribe controlled drugs without access to relevant information from your records, except in an emergency.
• Records in English, or with a translation.
• Photo ID, usually your passport. GMC guidance expects robust identity checks when doctors prescribe remotely.
• Details of your doctor at home, and your consent for the clinic to contact them and tell them what it prescribes. GMC guidance asks doctors who aren't your usual doctor to share information this way. It says it may not be safe to prescribe if information can't be shared.
• A list of everything you take, including any cannabis-based medicine you use at home and your dose. NICE guidance asks prescribers to take current and past cannabis use into account.
• The UK address where you'll be staying, and a way to reach you in your own time zone.

You may still be at home when a video consultation takes place. If so, GMC guidance asks UK doctors to consider whether they need to be registered in the country where you are. It also asks them to think about how your condition will be monitored. Clinics handle this differently, so it's worth asking. In the United States, the HIPAA Privacy Rule gives you the right to a copy of your medical records.

How long does it take, and how long does a prescription last?

Allow weeks, not days. Gathering records, having them translated and a clinic's own checks all take time. In my experience, a month or more from first contact isn't unusual, especially if records need chasing.

A UK prescription for a cannabis-based medicine has to be dispensed within 28 days of the date on it. NICE guidance says controlled drugs should be prescribed for no more than 30 days at a time, except in exceptional circumstances. So a longer stay means follow-up reviews and repeat prescriptions, and clinics usually charge for reviews.

What if I'm coming to work, or staying longer?

Some people live here for a while, for example to work or study. The Home Office expects them to bring no more than three months' supply of a controlled medicine. After that, it expects them to see a UK clinician for further supplies. It says the cost of UK healthcare is unlikely to count as an exceptional reason for a licence to bring more.

If your visa needed the immigration health surcharge, you can use the NHS from the date your visa starts. In England, anyone can register with a GP surgery, and visitors can register as temporary patients for up to three months. In Scotland, NHS inform says people coming to work or study should register with a GP practice as soon as they arrive.

Registering with a GP doesn't change who can prescribe a cannabis-based medicine. That's still a specialist's decision, and it's nearly always private. A private clinic will usually ask your permission to tell your UK GP what it prescribes. That's also what GMC guidance expects.

At work, THC from a prescribed medicine shows up on drug tests. Your employer's drug and alcohol policy matters, especially in safety-critical jobs. The guide to work, disclosure and workplace testing covers what to tell your employer and where you stand.

What are the rules while I'm in the UK?

You might have a prescribed cannabis-based medicine while you're here, from home or from a UK prescriber. If so, the same rules apply as for UK patients.

• Keep it in the pharmacy packaging with the label on. Carry a copy of your prescription, a letter from the prescriber if you have one, and ID that matches.
• Use it only as prescribed, and never smoke it. Smoking a cannabis-based medicine is against UK law, with or without a prescription.
• It's for you alone. Don't share it or give any to anyone else.
• Keep it somewhere safe and out of reach of children, including in a hotel room or holiday let.
• Cannabis that hasn't been prescribed to you is illegal to possess in the UK, whatever you use it for.

Driving is where visitors are most likely to get caught out. In England, Wales and Scotland it's an offence to drive with more than a set level of certain drugs in your blood, including THC. There's a defence if the medicine was prescribed to you and you took it as directed. That defence doesn't cover you if you're impaired. And driving while unfit through drugs is an offence anywhere in the UK. Read the driving guide before you hire a car.

If you feel unwell while you're here, call NHS 111 (NHS 24 on 111 in Scotland) for urgent advice, or 999 in an emergency.

Can I take it home with me?

Often not, so it's worth planning to use only what you need while you're here. A UK prescription only answers UK law. When you leave, the Home Office says you should be able to prove the medicine is yours. But the country you're going to decides whether it can come in, and so does every country you pass through on the way. The table shows what four countries' official guidance says.

For the United States, my reading of the April 2026 rule is that a medicine prescribed in the UK is neither of those things. So under federal law it stays in Schedule I. For Australia, the transit risks above apply on the way home too. For anywhere else, check with your own country's authorities before you travel, starting with the International Narcotics Control Board's country list.

Anything you don't use can go back to a pharmacy. NICE guidance says people should be told they can take unwanted controlled drugs to a community pharmacy for safe disposal. Don't post it home or ask anyone to carry it for you. The guide to travelling abroad with your medicine has more on paperwork and packing.

There are more plain English guides, including one on how the UK system works, on the patients and carers page.