Diabetes Mellitus: precautions to take during the summer
Do you suffer from Diabetes Mellitus and are you going to travel?
Summer is a time when we should all take special care to avoid certain health complications. However, for people suffering from chronic illnesses, and especially those with Diabetes Mellitus, these precautions must be redoubled.
Good nutrition and good hydration are, first and foremost, essential.
Chronic diseases: general care
In fact, anyone suffering from a chronic illness should take special care whenever they plan to go on vacation:
- To take medication in sufficient quantity for the days you will be away and some more (roughly double the amount, to prevent any setbacks that may require a longer stay);
- find out about the health resources and its operation in the destination location (hospital care locations or clinics), for any medical emergency situation;
- make a prior consultation with the attending physician to find out if it is necessary to make any adjustments to the medication;
- do the traveler consultation, if the destination requires it;
- take the European health insurance cardYou can apply for this card free of charge through Segurança Social Direta (you only need to confirm the participating European countries);
- carry the medication with you on the plane (if traveling using this mode of transport). On the one hand, the temperature in the hold is ideal, which could damage the medication; on the other, there is a possibility of losing your luggage.
- take due medical statement (especially for some countries), in Portuguese and English;
- have with you a card with a record of all medication and with the known diseases, in English and Portuguese;
- ponder a health insurance on vacation (depending on each case, the destination in question, the activities in view, etc.
- have a contact telephone number in case of emergency.
Diabetes Mellitus: specific care
For people with diabetes mellitus, other precautions are also essential. First, if you plan to travel, you should bring blood glucose test strips, ketones, pump consumables, a blood glucose meter (2) with batteries, a cable, and a charger.
On the other hand, if you take medications that can cause hypoglycemia (insulin, sulfonylureas), you should try to avoid hypoglycemia. Therefore, you should:
- always take the glucagen (injectable; there is also a nasal option) and packets of sugar, orange juice, water, bread, toast, fruit;
- pay attention the number of hours without eating and physical exercise that you may be planning to do – the most sensible option would be to always take a packed lunch;
- knowing how to do it correctly correction of hypoglycemia and inform the people they travel with (15g sugar or 200mL of sweetened juice, 15 minutes, repeat the procedure until the value is corrected) and eat slow carbohydrates with a protein/good fat; check back more frequently throughout the day;
- monitor blood glucose frequently (for example every 3 hours); always carry it with you blood glucose/ketone test strips and lancets in (more than) sufficient number;
- pay attention to the time zones and schedule in advance consultation with the attending physician to plan the trip in the best way;
- complaints to watch out for: weakness, hunger, trembling, cold sweats, palpitations, paleness, blurred vision, headache, irritability, mental confusion;
- do not expose insulin directly to the sun (store it in thermal bags or suitcases but never place it in contact with ice);
- do not expose the blood glucose meter or test strips to the sun;
- If you use an insulin pump and have disconnected it, you should not leave the device or catheters exposed to the sun.
Special care with alcohol
Take special care with the alcohol intake, which can lead to hypoglycemia if the stomach is empty or hyperglycemia when taken with meals (alcohol has calories and sugar, in addition to stimulating food intake).
Excessive alcohol consumption can cause hypoglycemia, especially in people with type 1 diabetes mellitus. Avoid drinking alcohol after exercising, as you are even more prone to hypoglycemia.
An alternative could be to drink slowly, mix with water or ice (bottled), moderate your intake, and always accompany it with food.
Diabetes Mellitus: recommendations for hot days
Regarding the pphysical exercise practice, You should opt for comfortable clothing and footwear (ideally closed-toe leather shoes, seamless cotton white socks). Ideally, you should exercise out of the sun, early in the morning or late in the day, when the temperature is milder (if you can combine it with good ventilation or air conditioning, even better).
As for sunscreen, In addition to all the usual precautions, sunburn should be avoided, as this can increase blood glucose levels.
In diabetics, the hydration is a fundamental issue. Therefore, hydrate yourself frequently, even if you're not thirsty (after all, thirst already means dehydration). If your diabetes is uncontrolled, there's a greater risk of dehydration; on hotter days, the risk will be even greater.
The kidneys increase the amount of urine, with the aim of eliminating excess sugar, which leads to a greater excretion of water from the body (for this same reason, when diabetes is uncontrolled, one of the most frequent complaints is polydipsia, excessive thirst).
You should be particularly attentive to complaints such as dry mouth, dry eyes, headache, dark urine, feeling of weakness, fainting.
People taking diuretics or other medications that increase the risk of dehydration should be aware of this issue. Avoid sugary drinks or soft drinks (which further increase dehydration due to the sugar content). Avoid alcohol and coffee, which stimulate diuresis (urine excretion).
Diabetics: watch your feet!
Keep an eye on your feet by wearing shoes whenever possible. Sensory peripheral neuropathy results in decreased sensation, which can lead to burns and other injuries (inadequate footwear/failure to inspect footwear).
Additionally, since open-toed shoes are worn in the summer, there is a greater risk of injuries, insect bites, or abrasions.
You should check your feet daily, wear white socks (to check for any exudate or blood) or, if necessary, ask someone to inspect your feet.
Heat strokes
It is also important to note that heat strokes may be more likely to occur if there is a vascular or nervous complication of Diabetes at the level of the sweat glands (they do not produce sweat, which means the body does not cool down properly).
If you have Diabetes Mellitus and are going on vacation, pay special attention to these recommendations. Take care of your health and make an appointment with a doctor today. specialist in Endocrinology.

Dr. Selma Souto
- She has a degree in Medicine with a specialization in Endocrinology and Nutrition.
- She was a guest lecturer at the Faculty of Medicine of the University of Porto.
- He is currently Vice-President of the Portuguese Society of Endocrinology, Diabetes and Metabolism (2024-2026).
- He is a member of several national and international scientific societies in the field of Endocrinology, Diabetes and Obesity.
- Author and co-author of more than 20 book chapters in the area of Obesity and Diabetes.