Pheromones are substances secreted and received by individuals of the same species, eliciting a specific reaction — in the case of sexual pheromones, a sexual one. Their characteristic feature is their lack of odor. They are produced, among other places, by the skin [eccrine glands throughout the skin, apocrine glands — mainly under the armpits, in the groin, around the genitals, anus, and mouth], and are also present in other secretions [semen, vaginal secretions, saliva].

Pheromones are a key element of the so-called ‘chemistry of love’ and trigger: feelings of attraction toward a given person, falling in love, euphoria, and they facilitate the achievement of orgasm. They are called the ‘love drugs’. Recently, they have been more appreciated and utilized to enhance erotic attractiveness and even in the treatment of desire and sexual arousal disorders.

One of the pathways of their transmission is a kiss. Pheromones act through the vomeronasal organ, beyond our conscious awareness. They influence the brain’s alpha rhythm, hormone levels, and neurotransmitters. In humans, they act on different levels, e.g. man–woman, man–man, woman–woman, parent–child.