One of the basic rules is to pack double the amount of medication for the duration of the trip and carry all medicines in your hand baggage.
In addition to the prescription, you need a doctor's certificate if your medication includes injections.
The air pressure in an aeroplane cabin is equivalent to the conditions at a height of roughly 1.5 km.
You should discuss with your doctor before flying, especially if you suffer from circulatory disorders or have recently had a heart attack or a cerebrovascular event.
After any abdominal surgery, I'd wait a couple of weeks before flying, as during these procedures some gas is introduced into the abdominal cavity, which may cause problems at a high altitude.
Likewise, if you suffer any strong trauma, you should reconsider the safety of travelling soon after, as it could increase the risk of pulmonary embolism.
Of course, the risk of embolism always exists on long flights, and it is therefore wise to wear flight socks, take some exercise, and drink plenty of water on longer flights.
Some documents are necessary at times
For some illnesses, airlines require a MEDIF (Standard Medical Information Form for Air Travel) form before the flight.
Such conditions include, for example, a recent heart attack, cerebrovascular disorders, traumas and surgeries, as well as chickenpox in the blistering stage.
As a general rule, personal oxygen equipment and CPAP equipment are allowed on flights but always require approval from the airline. While you are at it, remember to ask about their inverter facilities, as it's not included in the standard equipment of all aeroplanes.
An inverter transforms direct current into alternating current and can be necessary to run appliances such as oxygen equipment on an aeroplane.
Allergies are not understood everywhere
Dialysis patients have to carry a travel plan that includes information on their prearranged dialysis facility.
It’s generally a good idea to find the contact details for the nearest doctors and hospitals before you travel. And it goes without saying that a comprehensive travel insurance policy is the best possible travel companion.
Travellers with limited mobility can ask for help to cope with the long walking distances at airports, and most large airports have wheelchairs and assistance available.
In Finland, many suffer from various food allergies that may cause difficulties when taking distant travel to countries where allergies or their seriousness may not be understood.
If you have any doubt, I'd advise you to skip a dessert if you can't be sure it doesn't contain any nuts.