An Aylesbury publican claims the problem of people having drinks spiked has been getting worse over the summer.
The device aims to make drink spiking more difficult
Would-be muggers or men with sexual motives have been slipping drugs or alcohol into some people's drinks.
Aylesbury Pubwatch working with local police has already handed out 1,000 "Alcotop" devices to drinkers.
These are plastic stoppers which fit over a bottle to protect it from contamination and to raise awareness of the problem of spiking.
Cian McMonagle, who runs the Hogshead in the town centre, says he has seen the effects of spiking too often.
Protect your drinks plea
"Young people get dizzy and unaware of what they are doing or what is going on around them.
"It's better to protect your drink in some way and then you do not become vulnerable to attack - you stay safe," he said.
Alcotop were "road-tested" by university students in Essex and Oxford.