Reports of drink-spiking have trebled over the past three months in Merseyside, officials have said.
Nearly 200 cases were reported to police in February, compared with 68 in November, a report to Liverpool City Council has said.
There were four arrests from the 198 reports made, but all resulted in no further action being taken.
The report said 37 cases remained under investigation and will be "progressed through to finalisation in due course".
Drink-spiking incurs a maximum 10-year prison sentence in the UK.
Last autumn, the Night Time Industry Association said reports of drink-spiking had risen across the UK, which prompted many student groups to boycott clubs and bars.
Some venues and police forces brought in extra safety measures after campaigners called for more protection.
In October, Merseyside Police said it had increased officers on the streets "tasked with identifying potential perpetrators who are displaying signs of predatory behaviour".
A recent report to the council's neighbourhoods select committee said a "proactive" policing plan was in place every weekend to "protect vulnerable people, identify potential offenders and support victims", the the Local Democracy and Reporting Service said.
Its chair, councillor Joe Hanson, said the number of reports was "obviously a grave concern but the cabinet are working hard with partner agencies to see what we can do to come up with a solution".
"As a ward councillor, I'm aware of young people having their drinks spiked and I've got kids as well, my daughter spends time in town, so as a parent I'm concerned as well," he added.
In December, the council's premises licensing team received £5,000 to run an awareness campaign and provide an initial 2,000 drink-testing kits to bars and clubs.
More than 125 premises were provided with training on how to use drug detection kits and have also been supplied with awareness posters.
Policing of licensed premises will continue throughout the year, as part of the "Drink Less Enjoy More" campaign, the report said.
This article was written by BBC News (17th March 2022).