Sunstroke: Symptoms, causes and treatment. What to do immediately during a heat wave

Sunstroke is the most common type of heatstroke, in which the body overheats, due to prolonged exposure to the sun and is unable to regulate its internal temperature. Sunstroke can last from a few hours to 2–3 days, with the first few hours being extremely important for treating the most critical symptoms and preventing more serious complications.

Sunstroke or heatstroke: What's the difference?

The two terms are often confused. Sunstroke is caused specifically by direct exposure to sunlight, while heatstroke is the more general and more serious condition of the body overheating (with or without sunlight) and is considered a medical emergency. In practice, severe sunstroke can progress to heatstroke, which is why prompt treatment is critical.

Symptoms of sunburn

If you’ve experienced sudden dizziness and unsteadiness, an intense urge to vomit, or a “heavy” feeling in your head, during your summer vacation, then you’ve probably spent too much time in the sun, especially during midday and afternoon hours, which are important to avoid. 

The most common symptoms of sunstroke include:

• Dizziness and difficulty concentrating.
• Weakness and low energy.
• Ringing or buzzing in the ears.
• Dry mouth.
• Dry skin.
• Gastrointestinal disturbances.
• Intense urge to vomit.
• Headache or migraine.
• Muscle weakness.

Sunstroke and fever

Sunstroke may be accompanied by a mild fever. In more severe cases, high fever, convulsions, or loss of consciousness may occur, in which case immediate medical attention is required.

Treatment & First Aid

According to the Greek Red Cross, the steps we should take if any of the above symptoms appear are as follows:

1. There’s no need to panic or try to reduce the temperature, using extreme methods (e.g., ice, a very cold bath).
2. Move out of the sun and find a cool, shaded spot.
3. Immediately remove heavy, sweat-soaked clothing.
4. Cool off with a wet towel or compress at regular intervals.
5. Avoid any beverages that can worsen dehydration caused by sun exposure, such as coffee or alcoholic drinks.
6. Begin rehydration immediately, by alternating between water and electrolytes in small amounts at regular intervals, avoiding large amounts of fluids all at once, to help address dehydration more effectively.

In case of severe sunstroke (heatstroke), a high fever (above 38 degrees), convulsions, and loss of consciousness—a condition that requires immediate medical attention and a visit to the nearest hospital or health center.

Sunburn in children & vulnerable groups

Children, adolescents, the elderly, and people with cardiovascular disease, diabetes, asthma, or other chronic conditions are at increased risk. For this reason, they require greater attention, early recognition of symptoms, and immediate implementation of appropriate countermeasures.

Prevention is better than cure. What steps we need to take to protect ourselves?

Between 2000 and 2019, approximately half a million deaths per year (!) were recorded due to high temperatures, with 36% of these occurring in Europe, a fact that sounds the alarm about accelerating climate change and compels us to arm ourselves with knowledge so that we can take the necessary measures to prevent and protect ourselves from potential — and now even confirmed — heat waves during the hot months of the year.

• Choose comfortable, light-colored clothing. If you sweat heavily, it’s important to change your clothes, as this further helps the body regulate its temperature.
• Choose a shaded and cool environment, especially during midday hours.
• Avoid strenuous exercise outdoors.
• Stay hydrated at all times and check the color of your urine to prevent severe dehydration, which increases the risk of moderate and/or severe sunstroke. Urine should be off-white to light yellow in color, which is a sign of good hydration.
• We wear a hat, sunglasses, and sunscreen, which we reapply frequently, especially as the temperature rises and as soon as we get out of the water.
• Choose seasonal fruits and vegetables that are high in water content, especially when you know you’ll be spending many hours outdoors.
• Choose salted nuts, especially if you have low blood pressure.
• Avoid very heavy meals and opt for light ones instead, especially during peak heat hours.

In Conclusion

Sunburn is a very common occurrence in our country, where we need to be mindful of the sun’s rays, especially when we’re at the beach, but also when we’re outdoors without protection. It is important to be aware of its symptoms and to know when to seek medical advice. However, there are many ways to prevent it, such as staying hydrated and protecting ourselves from prolonged sun exposure.

Have a great summer vacation, everyone—with plenty of shade, sunscreen, and ice-cold water!

Scientific References

Al-Ameri, G., Salem, W., Alessai, G., Hellboob, M., Alhatemi, M., Nashrah, U., & Shaikh, N. (2024). Acute Management of Heat Stroke: Facts and Figures. In Heat Illness and Critical Care. IntechOpen.

Heat and Health, World Health Organization (WHO)