A couple have invented a device aim at stopping drink spikers after their son was targeted in a pub.
The device aims to make drink spiking more difficult
Nicci and Dean Welsh's teenage son apparently had his drink spiked in Skegness as he waited to meet a group of friends last summer.
The "Alcotop" fits onto bottles and snaps shut making drink spiking harder.
It has been endorsed by the Roofie Foundation, an agency dealing with drug rape and sexual abuse caused through drink spiking.
The Welshes believe their son Daniel, then aged 17, suffered the effects of a spiked drink last August.
Dean Welsh said: "He wasn't even in a club - he was in a bar to join some friends and that's the last thing he remembers.
"The next thing he knew he was sat in a doorway at about half past four in the morning - minus his new mobile, a new pair of Rockport boots and the wages he'd picked up that day.
"When he got home he told me he hadn't been drinking, and he didn't smell of alcohol."
A publican friend of the family suggested Daniel's drink may have been spiked.
Mr Welsh added: "It's something we wouldn't like to see happen to someone else's child - it could have been worse, and we want to stop it happening again."
The invention fits over the top of a bottle with a lid a person can snap shut when they are not actually drinking.
"It gives the message that person drinking it is aware of the possibility of danger - and hopefully it will prevent tampering.
"But we're not saying it's completely tamper-proof - we're putting a message in the packaging literature to make sure you keep an eye on your drink at all times."
Alcotop is being "road-tested" by university students in Essex and Oxford.