Two people have been arrested as part of an investigation into spikings in Nottingham.
A man has also been arrested in Lincoln as part of an inquiry into similar allegations there.
In both cases, the police say the suspects have not been linked to incidents which involve chemicals being administered via a needle.
Sky News reported how women were feeling ill and blacking out after allegedly being attacked with needles in cities such as Nottingham, Liverpool, Cardiff, Manchester, Leeds and Newcastle.
The two men in Nottingham – aged 18 and 19 – were detained on Friday morning on suspicion of conspiracy to administer poison with intent to injure, annoy or aggrieve.
Superintendent Kathryn Craner, of Nottinghamshire Police, said: “I would like to reiterate that these arrests have not been made in connection with a specific case or incident reported to us over the last few weeks of both drink spiking and spiking by a needle.”
The man in Lincoln, aged 35, was arrested in the early hours of Friday morning on suspicion of possession of drugs with intent to administer them.
Police said the suspected offence “doesn’t involve a needle”.