Charities and the police are warning drink-spiking can take place anywhere with reports of unsuspecting victims even being targeted at weddings and funerals.
Norfolk Police has warned there could be a lengthy prison sentence for anyone caught spiking drinks.
And Dawn Dines, chief executive and founder of Stamp Out Spiking UK and StopTopps, says spiking can happen at any time and any place.
Her charity has recently had reports of a guest carrying out a spiking at a funeral, as well as reports of the crime at weddings and picnics.
Ms Dines said: "Drink-spiking can happen to anybody and it does not just happen at dark pubs and nightclubs.
"We ask people to be alert and to watch out for their own drink and other's.
"I have heard this has been happening over the last 17 years so I am so happy the word is now getting out because it has been underreported for so long."
The warning comes after officers swarmed on a city centre pub as customers looked on sipping their drinks in the garden.
Police attended the Wetherspoon's Bell Hotel in Orford Hill around 4pm on Thursday with three police cars and multiple cops at the scene for a few hours.
A spokeswoman for Norfolk Police said: "Police were called to a business premise in Orford Hill in Norwich at approximately 4pm following reports of an assault and alleged drink-spiking.
"No arrests have been made and enquiries are ongoing. The victim suffered no injuries as a result of the incident."
Chief inspector Ed Brown said: “We take spiking incidents seriously and have been working with the night-time economy to identify those who are responsible.
"We are carrying out targeted patrols in key areas to create a safe space for people to enjoy themselves.
“We are working in partnership with the night-time economy to ensure we safeguard anyone who feels they are a victim of spiking.
"Anyone with someone they believe has been spiked should stay with them and seek medical attention if they deteriorate."
A spokeswoman for Wetherspoon said: "The police attended the premises and took the drink concerned with them for testing. Wetherspoon are assisting the police with their investigation."
Police have urged anyone who believes a crime is in progress to call 999.
Visit stampoutspiking.org for more information on Stamp Out Spiking UK.
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