Changing planes with medication: which stopovers count

You've checked the rules for your destination. But if your flight changes planes somewhere else, does that country's medicine law apply to you too?

It depends on the country, and on whether you leave the airport. Some authorities say plainly that passengers who stay airside are exempt. Others say their rules apply even in transit. Here's what the official sources say.

Exempt if you stay airside

These countries don't require their medication permit if you only change planes and don't go through immigration:

• Singapore. You don't need HSA approval for personal medication if you stay in the airport transit zone. Prohibited medicines, such as cannabis-based products, still aren't allowed, even in transit.
• United Arab Emirates. The Emirates Drug Establishment says transit passengers who stay inside the airport don't need its approval.
• South Korea. MFDS says no permit is needed if you only change planes and don't go through immigration.

If you leave the airport, even for a few hours, you're entering the country, and its normal rules apply.

The rules apply even in transit

• Hong Kong. The Drug Office says you need its approval for controlled medicines even if you're only transiting.
• The Philippines. Its drug regulation covers travellers passing through the country as well as those entering it.
• Argentina. If you're in transit with medicine containing narcotic or psychotropic substances, carry a legal document listing you, the medicine and your doctor's details, and show it to health or police authorities.
• Georgia. Passing through in transit with narcotic or psychotropic medicine, you need the same certified prescription, doctor's certificate and legalised document as for entering, presented with a customs declaration.
• Albania. Customs prohibits the transit of narcotics and psychotropic substances, as well as their import and export.
• Colombia. Bringing cannabis into Colombia without a licence is a crime "even in transit."
• Qatar, Sri Lanka and Cambodia, for cannabis. UK government travel advice warns of long prison sentences for illegal drugs, including cannabis, "including when transiting through the airport", and says their airports scan transit passengers' baggage. In Qatar that includes even residual amounts.
• Taiwan, for e-cigarettes. On a short layover, declare e-cigarettes and e-liquids when you arrive. Customs keeps them at the bonded luggage counter and you collect them when you leave.

When the rule doesn't say

For medication at many hubs, including Doha and Tokyo, the official pages we've checked don't say how they treat passengers who only change planes. We don't guess. If your route goes through one of them, ask that country's authority before you fly, or plan to carry what its entry rules require.

Check your route

Trip Check now has a "Changing planes in" field. Add your stopover, and each item shows that country's transit rule where the authority states one, with the source and the date we checked it.