Frequently Asked Questions

faq-headerThe active ingredient in BullsEye Bug Repellent is IR3535®. It repels mosquitoes that may transmit Zika, Chikungunya, Dengue Fever, and West Nile Virus for up to 8 hours. It offers proven, strong protection when you need it most. Below are a few answers to some common questions you might have about IR3535®:

How does IR3535® work?
Insects use odors for their navigation in nature. There are various substances in nature which provide messages to insects. For example, there are substances which help mosquito males to find females or guide mosquito females to a host for blood feeding. ß-alanin is a natural substance which provide the gentle message to insects to keep away. This effect is named “repellent effect”. For the development of IR3535®, ß-alanin was modified to intensify this signal. Therefore, IR3535® is a repellent and causes insects to move away from treated skin, textiles and hair. Some repellents also show an insecticidal effect. That means some other repellents may kill insects after contact. However, IR3535® only provides a message to repel and does not attack the insect.
How can I find products with IR3535® in Pharmacies and other Shops?
Products with IR3535® are offered via pharmacies in some countries and via cosmetic shops, outdoor-shops, supermarkets and home improvement stores in other countries. “IR3535” is a short name (brand name) and not necessarily used for labelling all the time. We collected the chemical names and numbers which will help you to identify products which contain IR3535®:

    • IUPAC: 3-(N-n-Butyl-N-acetyl)aminopropionic acid ethyl ester
    • BPD notified Name: Ethyl N-acetyl-N-butyl-ß-alaninate
    • INCI: Ethyl Butylacetylaminopropionate
    • CAS number: 52304-36-6
    Is IR3535® safe?
    IR3535® only provides a message to insects and does not show any potential to kill insects. In addition, IR3535® is skin friendly and shows an excellent safety profile. This was confirmed by World Health Organization (WHO), Environmental Protection Agency (EPA in USA) and many other authorities world wide. IR3535® has been used in repellent products in Europe for more than 30 years and there were never reports about serious side effects. If you are interested in more details, you will find the original publications of WHO and EPA under the “other webpages” button.
    Are products with IR3535® suitable for children?
    Yes. Many authorities (as well as WHO) investigated the safety of IR3535® in detail. IR3535® received an excellent safety grading and is specifically highlighted when children’s use is mentioned.


          The French Ministry of Health recommended IR3535® for children and pregnant woman during chikungunya epidemics on Reunion (January 31, 2006).


          IR3535® is used today worldwide in many specific children’s repellent products.


          In most cases, a product label will provide you good instructions for children’s use of the specific product. The application of repellents to children should be performed by adults at all times. You will find excellent use instructions for children on this web page:

    Center for Disease Control

          (search for “Insect Repellents“).
    How often should I reapply products with IR3535®?
    The efficacy of repellents products depend on:

    • Concentration of active substance (like IR3535®)
    • Insect species which shall be repelled
    • Formulation (hydroalcoholic spray, lotion, sun screen combo etc.)
    • Season of the year and weather (warm weather with high humidity increase – for example, mosquito population and biting)
    • Activity of person using the repellent (sport activities lead to sweating and diminish protection time; rubbing or water contact may remove the repellent from skin and the protection)

    The best information for protection times and reapplication under normal use conditions is provided on the label of a product. Such product information has to be proven by testing under standardized conditions in many countries. If you are interested in such testing guidelines, you will find them under the “Efficacy Testing of Repellents” button. In addition you will also find a summary of the IR3535 performance.

    How can I protect myself against insects and sun?
    Combo products for insect and sun protection with IR3535® are available in some countries (USA, UK, Brazil and Argentina). If no combo product is available, use a sun protection product first and 10-15 minutes later the repellent product. If you apply the sun protection product over the repellent, the efficacy of the repellent might be reduced. The insect cannot “smell” the repellent anymore in a sufficient way.
    Can I also protect my clothes against mosquitoes, ticks and flies with IR3535® products?
    Some products with IR3535® are intended for use on clothes in addition to the skin. Please follow use instructions of this product for the application. We would recommend to test it out on a non-visible part of the textile before you actually use it. IR3535®, like some other repellents, is not compatible with some synthetic materials.
    The protection of clothes against insects can be important in high risk areas. Some mosquitoes can bite through clothes and ticks can stay undiscovered for hours on other parts of clothing. The ticks could later move to unprotected skin areas.