Pheromone
Pheromones were chemicals produced by organic lifeforms. They were predominantly related to sex and sexuality. In weevils and moths, the female produced pheromones first, which signalled the nearest male to excrete his own chemicals in response. The two insects would then come together and mate. (PROSE: Syntax) In Sheffield, the pheromones of mutated spiders disrupted the behaviour of normal spiders. (TV: Arachnids in the UK)
In the 21st century, a gaseous entity possessed a human woman, Carys Fletcher, forcing her body to develop a series of pheromones that were irresistible to other humans. (TV: Day One) Love wraiths put a "spell" on their victims using hypnotic pheromones, which caused the humans to see the wraith as an impossibly attractive member of their own species, rather than as the wraith's true, "ghastly" appearance. (WC: Stacey Facade, HOMEVID: Lauren Anderson)
By the 51st century, humans had evolved to produce more highly evolved pheromones, which made them more sexually attractive than their ancestors. (TV: Fragments)
By the time of the 309th Intergalactic Song Contest, Angvians' pheromones were so strong that they could even manipulate a Time Lord's sensibilities. (AUDIO: Bang-Bang-a-Boom!)
Andrea Quill and Ballon went to Arn Heaven to collect arn pheromone in order to remove the arn from Quill's brain. (TV: The Metaphysical Engine, or What Quill Did)
The Builders communicated through sophisticated pheromone secretions. (PROSE: Primitives)
The Fourth Doctor used pheromones to collect a Gadot. (AUDIO: Waiting for Gadot)
In 2050, K9 detected Jixen pheromones in a sample of mucus left behind by a Jixen warrior. (TV: The Last Precinct)
On the planet Jora, a living, sentient language, the Syntax, was created out of scientists' attempts to create a pheromone language. (PROSE: Syntax)
Leechers fed by draining chemicals, including pheromones, from their prey. (COMIC: Ripper's Curse)
Chat took a pheromone shot, which changed her scent to that of a Veltrochni, to help her steal a Tzun data core on Veltroch. (PROSE: Mission: Impractical)
After she was converted into a human-Zygon hybrid, (HOMEVID: Zygon: When Being You Just Isn't Enough) Lor Anderson began to emit highly unusual pheromones which allowed Stacey Facade to trace her across London with ease after Lor tried to get away from Stacey. (HOMEVID: Lauren Anderson)