Boiled sweets were a type of confectionery from Earth used occasionally by the Doctor.
The variant of Nitro-9, Neo-Nitro, resembled boiled sweets and activated using saliva. (PROSE: Shadowmind)
To counteract the ill effects of time spillage on Jamie McCrimmon, the Second Doctor gave him one of his striped boiled sweets. When Jamie ate it he immediately felt better. (PROSE: Vortex of Fear)
Iris Wildthyme checked to see if she had a boiled sweet in her bag when a taxi servicing Bianca's passed through a wormhole. (AUDIO: The Wormery)
After healing Amy Pond's wounds from a Saturnyn bite, the Eleventh Doctor popped what appeared to be a humbug into her mouth. (TV: The Vampires of Venice)
When Rose Tyler was searching through the Doctor's pockets during one adventure, a packet of boiled sweets was one of the items she found. (PROSE: The Price of Paradise)