What should a travel first aid kit contain, and what medications to bring on a plane?

In an aircraft, there is reduced atmospheric pressure when flying at high altitudes. However, it is worth noting that the pressure in the aircraft cabin is regulated to keep it at a level corresponding to an altitude of about 1800–2400 meters above sea level (in commercial aircraft). Nevertheless, there may still be some health problems associated with this phenomenon.

Changes in cabin pressure, especially during takeoff and landing, can lead to unpleasant discomfort in the ears. When the atmospheric pressure changes and the inner ear space is unable to compensate for the external pressure (for example, due to a blocked Eustachian tube), pain, a feeling of clogged ears and, in some cases, even damage to the eardrum can occur.

Ear blockage can lead to a temporary hearing problem and a feeling of fullness in the ears, which is unpleasant but usually harmless. To relieve the pain, chewing gum, sucking on candy or using the so-called Valsalva maneuver (gently blowing air through a blocked nose) can help.

An increase or decrease in pressure can worsen sinus-related discomfort, especially in people suffering from colds, allergies or sinus infections. As a result, pressure within the sinuses may not equalize properly, causing pain and discomfort. The change in pressure can also impede the natural cleansing of the sinuses, which can promote infections.

Although the cabin pressure is regulated, it is still lower than at sea level. For people with respiratory diseases (for example, asthma, chronic obstructive pulmonary disease — COPD), lower pressure can worsen gas exchange in the body, resulting in challenged breathing, a feeling of shortness of breath or reduced performance. It's a good idea to carry basic breathing medications or specialized equipment then, which must be reported to the flight crew in advance.

Reduced physical activity on long-haul flights (especially on transatlantic routes) combined with low pressure can lead to an increased risk of blood clots in the veins (the so-called Economy Class Syndrome). People with circulatory problems such as varicose veins, obesity, or a tendency to blood clots should take precautions, such as exercising their legs regularly, avoiding sitting in one position for long periods, and consulting a doctor before flying.

Changes in pressure can affect balance, causing dizziness, especially in people who are prone to problems with the vagus (for example, those with Meniere's disease).

People with heart conditions, such as heart failure, hypertension, or after a heart attack, may be more vulnerable to the effects of reduced cabin pressure. In such cases, reduced oxygen content can affect cardiovascular fitness, increasing the risk of compromised health during flight.

Tranquillizers (such as sleeping pills, benzodiazepines or other agents that act on the nervous system) can be used in some cases to reduce the anxiety associated with flying (the so-called fear of flying) or to help you fall asleep on long flights, but their use carries certain risks and requires caution.

It is definitely worth consulting your doctor before deciding to use sedatives during a flight, especially if you experience any health problems (for example, heart disease, respiratory disease, blood pressure problems).

Your doctor can choose the right dose and type of medication that will be safe in your case and will not cause unwanted side effects. It is important not to experiment with new medications, especially before air travel. It may be effective to simply take a natural substance such as melatonin.

Melatonin is a natural hormone produced by the pineal gland in the brain that regulates sleep and wakefulness rhythms. It is used as a dietary supplement, especially to improve the quality of sleep, especially in cases of sleep disorders such as insomnia, disrupted diurnal rhythms (for example, jet lag after a time zone change) or sleep problems associated with shift work. Melatonin helps synchronize the sleep cycle with the body's natural biological rhythm, aiding in falling asleep. Melatonin's effects are mild, so it is considered a safe option compared to some sleep medications.

If the fear of flying is strong, some people are prescribed tranquillizers to help reduce anxiety. However, such drugs can cause drowsiness and impair the ability to react quickly, so they are not recommended for people who have no previous experience with them.

There are restrictions on carrying various substances, including medicines, due to passenger safety and customs and health regulations. Below you will find a list of medications that should not be brought on board a plane or that require special precautions.

Drugs containing narcotics or psychotropic substances, such as opiates (morphine, codeine), amphetamines, barbiturates, benzodiazepines, may be prohibited or require special permits. Prescription drugs that contain substances banned in the destination country (for example, morphine, fentanyl, codeine) may be confiscated if you do not have the proper documents proving their legality.

According to international aviation security regulations (for example, ICAO, TSA), passengers can only bring liquids on board in containers up to 100 ml. Medicines in liquid form that exceed 100 ml may be confiscated unless you have the appropriate documents (for example, a prescription) and report them to the relevant airport security services.

Drugs that require cold storage (for example, some insulins, vaccines) may not be suitable for transport in the cabin of an airplane unless you have special refrigerated containers that provide the proper temperature. Make sure that the drugs you are transporting are properly packaged and can be stored according to the manufacturer's requirements.

Benzodiazepines and other sedatives can cause drowsiness or impaired responsiveness, which, combined with other factors such as changes in pressure, prolonged sitting or stress, can pose a risk during a flight. Using them without medical supervision can be dangerous. These drugs may also be classified as controlled substances in some countries, and transporting them without proper documentation can lead to legal problems.

Before travelling, it's a good idea to check whether a particular drug is allowed in the country you're travelling to. Many countries, especially in Asia and the Middle East, have strict regulations on transporting medicines. For example, some drugs containing codeine, tramadol or other painkillers may be prohibited. Customs regulations can vary from country to country, so it's a good idea to check local regulations before you travel.

Drugs that may react chemically with other substances (for example, certain antibacterial agents, disinfectants, antiviral drugs) may be prohibited from transportation under certain conditions. In some cases, for example, drugs in the form of aerosols or inhalation sprays may be considered unsafe if their capacity is too large, or they do not meet safety standards.

For prescription drugs, especially if they contain controlled substances, it is a good idea to carry the original prescription or a certificate from your doctor. This is especially true for drugs used to treat chronic illnesses (for example, diabetes drugs, high blood pressure, painkillers).

If you are transporting liquid medications (for example, insulin, eye drops), inform security services of their presence and present the appropriate documentation. Many airports allow you to carry more medications if you provide the appropriate documentation.