Piperonyl Butoxide (PBO) is a synergist that enhances the effectiveness of insecticides. It works by inhibiting enzymes in insects that can break down the insecticide, thereby increasing the insecticide's potency. PBO helps to prolong the effectiveness of the other active ingredients in the spray.

Permethrin is a synthetic insecticide from the pyrethroid family. It acts as a neurotoxin in insects by targeting their nervous systems. Permethrin disrupts the normal functioning of nerve cell membranes, leading to paralysis and ultimately death of the insects. It is effective against a wide range of pests, including flies, mosquitoes, ticks, and other biting insects.

Pyrethrin is a natural insecticide derived from chrysanthemum flowers. It is known for its quick knockdown effect on insects. Pyrethrin affects the nervous systems of insects, causing paralysis and death. It is particularly effective against flying insects such as flies and mosquitoes.

Citronella Oil is a natural essential oil and works by masking scents that are attractive to insects, making it harder for them to locate their targets. It is particularly effective against mosquitoes, flies, and other flying insects. While it doesn't kill insects, it can help deter them from approaching humans, animals, or specific areas.

Together, these active ingredients in Flygon GOLD work synergistically to repel and control a variety of insects that can bother horses. The combination of PBO, permethrin, and pyrethrin provides a broad-spectrum approach to insect control, targeting different stages of insect life cycles and offering extended protection against biting pests.

It is important to follow the product's instructions and use it safely and responsibly according to the guidelines.