
Pheromones produced by Orion females
A pheromone was a chemical secreted by a lifeform that had an effect on another lifeform.
Locator bombs worked by homing in on an individual's pheromones. (DS9: "The Nagus")
Orion slave girls secreted a highly potent pheromone that accelerated the metabolisms of males of many species, raising adrenaline production to dangerous levels. It caused aggression and a form of delusion that made the males susceptible to suggestion. The pheromone caused headaches in Human females and disrupted the sleep cycle of Denobulan males; Vulcans, however, were immune. The pheromone's effects were cumulative; the longer one was exposed, the more pronounced the results. In 2154, Doctor Phlox of the Enterprise NX-01 theorized that the pheromone acted as a defense mechanism against competition. (ENT: "Bound")
Denobulan females emitted powerful pheromones during their mating season. Male Denobulans often became combative during this time, and mating could require medical supervision. (ENT: "Dear Doctor", "A Night in Sickbay", "Bounty")
During the finiis'ral, the final stage of a Kriosian empathic metamorph's bonding, they produce elevated levels of what Humans would call pheromones. (TNG: "The Perfect Mate")
In 2370, Captain Picard used pheromones from Deanna Troi to lure Worf while they all suffered from Barclay's Protomorphosis Syndrome. (TNG: "Genesis")
Ramurans produced pheromones that prevented the formation of long-term memory engrams in other species they interacted with. (VOY: "Unforgettable")
In 2375, One, an advanced Borg drone with 29th-century technology, detected an elevated pheromonal response in a USS Voyager crewmember, indicating that she was afraid of him. (VOY: "Drone")

Queen Arachnia's pheromone vial
In The Adventures of Captain Proton holoprogram, the character of Queen Arachnia had, in her possession, a small vial of her pheromones, which she could use to seduce and control others. Kathryn Janeway, as Arachnia in 2375, used these pheromones against the character of Lonzak. (VOY: "Bride of Chaotica!")