When the warm weather arrives, the combined application of sunscreen and insect repellent spray becomes a reflex for many holidaymakers, parents and outdoor enthusiasts. But is this double protection really effective? A recent CNRS study, published in the journal
The CNRS study: an innovative method, clear-cut results
French researchers have conducted an experiment using ex-vivo human skin biopsies. By analyzing the combined effect of sunscreens and mosquito repellents, they used an artificial intelligence tool called
The verdict is clear: UV protection is reduced when sunscreen is combined with certain repellents. In particular, two-in-one products (sunscreen + repellent) show highly variable efficacy. The study therefore underlines the need to apply these products according to precise protocols in order to maintain their respective efficacy.
Official recommendations: what do the experts have to say?
Health authorities generally recommend applying sunscreen first, and waiting at least 20 minutes before using an anti-mosquito spray. This allows the cream to penetrate the skin properly and form a stable protective barrier.
In Canada, products combining UV protection and repellent are even banned, as their efficacy times do not coincide. While sunscreen must be renewed every 2 hours or after each swim, repellents generally last longer.
Application: respecting a strict order
To ensure effective double protection, follow the steps below:
- Apply sunscreen (SPF 30 minimum, ideally 50).
- Wait 20 minutes for proper absorption.
- Then apply the anti-mosquito spray to exposed areas, avoiding the face.
This protocol reduces the risk of negative interactions between the two products. It’s also a good idea to reapply sunscreen after swimming, or every two hours, but without systematically reapplying repellent.
Beware of photosensitizing products
Some ingredients in natural repellents or post-bite skin care products can cause skin reactions to the sun. This is particularly true of :
- Citrus essential oils (lemon, orange, bergamot).
- Certain topical antihistamines, such as isothipendyl hydrochloride.
It is therefore preferable to avoid these components before prolonged exposure to the sun, especially for sensitive skin.
Which products are right for you?
For children:
- Choose a high-protection (SPF 50), fragrance-free mineral sunscreen.
- Use a special children’s repellent, without DEET or with a very low concentration.
For active holidaymakers:
- Water-resistant creams, renewable every two hours.
- Mosquito repellent spray based on IR3535 or icaridine.
For sensitive skin:
- Choose hypoallergenic formulas, without alcohol or essential oils.
- Always test products on a small area before general application.
Alternative without skin contact:
- To completely avoid the risk of interaction between spray and cream, the use of Qista by Mosquizen mosquito repellent solutions is a safe and effective alternative. These ecological terminals act remotely, protecting a defined perimeter without application to the skin, thus preserving the effectiveness of sun protection products.
- Read also: The Qista by Mosquizen ecological mosquito repellent terminal
Conclusion: a possible duo, but with conditions
Mosquito repellent spray and sunscreen are not incompatible, but combining them requires rigor and common sense. By respecting the order of application and waiting times, you can benefit from effective double protection. Be careful, however, with all-in-one products and photosensitizing ingredients. For vacations, it’s best to prepare a specific kit, adapted to each skin profile and destination.
Frequently asked questions
Can I use insect repellent and sunscreen at the same time?
Yes, but there must be a 20-minute gap between the two applications.
Are two-in-one products effective?
According to the CNRS, their UV protection effectiveness varies widely. So be careful.
Do I have to reapply the repellent every time I use the cream?
No, only if the repellent is short-acting. Follow the manufacturer’s recommendations.