How does fly spray work?

Understanding the Science Behind Fly Spray

Have you ever wondered how fly spray actually works? If you’ve ever dealt with pesky flies buzzing around, you know how annoying they can be. Fortunately, there’s a solution: fly spray. In this article, we’ll delve into the mechanics of fly spray and how it effectively keeps those bothersome insects at bay.

Understanding the Basics

Before we dive into the inner workings of fly spray, let’s start with the basics. Fly spray, also known as an insect repellent, is a specially formulated product designed to repel and deter flies. It typically comes in the form of a spray or lotion that can be applied to the skin or surfaces. The active ingredients work together to create a protective barrier against flies.

Active Ingredients

Fly sprays contain various active ingredients that act as repellents. The most common ones include:

DEET (N,N-diethyl-meta-toluamide)

This is one of the most widely used active ingredients in insect repellents. DEET works by interfering with the insects’ ability to detect the presence of humans or animals. It masks the scent that attracts flies, making you less appealing to them.

Other synthetical ingredients

There is a wide variety of synthetical ingredients (e.g.: Deltamethrin, Permethrin, Imidacloprid, Cyfluthrin, Bifenthrin) extensively employed as insecticides, each with its distinct mode of action. However, the common effect they have on insects is disrupting their nervous system.


Another effective ingredient, picaridin, works by repelling flies and other insects. It disrupts their ability to locate a potential food source by confusing their olfactory senses. Picaridin-based fly sprays are often favoured for their long-lasting protection.

Citronella Oil

Derived from the leaves of the lemongrass plant, citronella oil is a natural repellent that has been used for centuries. It produces an aroma that flies find unpleasant, deterring them from landing on surfaces or individuals.

Essential Oils

Some fly sprays harness the power of essential oils such as eucalyptus, peppermint, or lavender. These oils have potent fragrances that flies dislike, making them an effective natural alternative to synthetic repellents.

How Does It Work?

When you apply the fly spray, the active ingredients come into action. They create a protective barrier on your skin or the treated surfaces, making it unattractive or even undetectable to flies. These ingredients work in several ways:

Repelling Flies

Fly spray emits an odour or taste that flies find repulsive. This discourages them from landing on your skin, animals, or surfaces where the spray has been applied. The repellent effect can last for several hours, depending on the concentration of active ingredients.

Masking Attractive Scents

By masking the natural scents emitted by humans and animals, fly spray reduces the likelihood of attracting flies. It confuses their sensory receptors, making it difficult for them to locate a potential food source.

Disrupting Landing

Some fly sprays contain ingredients that make the surface sticky or slippery. When flies attempt to land, they encounter an unpleasant texture, deterring them from settling down.

In addition to traditional fly sprays, other forms of insecticides are available, such as fly baits and traps. Fly baits contain attractants to lure flies into them before poisoning them, while fly traps use sticky surfaces to trap and kill flies. These alternatives can be useful in situations where fly sprays cannot be used, such as in areas where food is being prepared.

Using a fly spray is essential in repelling and deterring flies, effectively reducing their persistent presence. It’s important to understand how fly spray works and choose the right product for optimal results. Whether you prefer synthetic repellents or natural alternatives, using fly spray correctly contributes to creating a fly-free environment for yourself and those around you. Remember the scientific principles behind its efficacy the next time you grab your reliable bottle of fly spray and enjoy a fly-free zone. However, if the fly problem persists despite your efforts, it’s highly recommended to seek assistance from a professional pest control service. They have the expertise and resources to address the underlying issue and provide effective solutions tailored to your specific needs.