Can you tell a drink has been spiked by its appearance?

A poster being shared on Facebook and Twitter offers advice on “how to recognise a drink that’s been spiked or tampered with”.

The poster says that signs of a spiked drink include: “change in colour”, “sinking ice”, “excessive bubbles”, and a “foggy appearance”.

Drink spiking involves either adding alcohol or drugs to drinks without the drinker’s knowledge or consent.

Full Fact spoke to experts who said that while the poster does offer some good general advice on being aware of your drink, there is no “foolproof” way to recognise whether a drink has been spiked, and it is not always possible to tell whether a drink has been tampered with through sight, smell or taste.

Professor Atholl Johnston, Emeritus Professor of Clinical Pharmacology at Queen Mary University of London, told Full Fact that with some drugs, such as LSD “you only need such a small amount that it would never change the colour, it would never change whether the ice sinks or not, it would never give you excessive bubbles, it certainly would never make it foggy.”

UK alcohol charity Drinkaware says: “If your drink has been spiked with a date rape drug it's unlikely that you will see, smell or taste any difference, no matter what type of drink you are having.”

An NHS fact sheet published in 2017 similarly says: “It is hard to tell if your drink has been spiked. The drugs are usually tasteless, odourless (no smell) and have no colour so you would not usually know.”

As well as “party drugs” like LSD and ketamine, so-called “date rape drugs” used in drink spikings include GHB (gamma hydroxybutyrate), GBL (gamma butyrolactone) and benzodiazepines (including Rohypnol).

Talk to Frank, the UK Government’s anti-drug advisory service, says that while GHB and GBL are often sold as a “colourless, oily liquid”, GHB has “almost no smell and a salty/soapy taste,” and GBL has “a very strong chemical taste and smell.”

Professor Johnston also highlighted the potential of some of these drugs to carry a distinctive taste but said, in many cases, the amount of these drugs being placed in a drink would be so small as to be unlikely to cause the drink to noticeably change. 

He told us: “There are a lot of very potent drugs out there where you're never going to detect [them]”.

Dr Richard Parsons, Senior Lecturer in Biochemical Toxicology at King’s College London, also told us that dark coloured drinks, or drinks with strong smells and tastes, may mask any traces of drugs like benzodiazepines, saying: “A lot of it is very, very context dependent. And very dependent on where the victim is, the environment, [and] what's going on around them.”

He added that while the poster itself was helpful in raising awareness, “what's more likely than not, [is that] there'll be no sign at all. And if there is a sign, it can be very difficult to pick that up in a dark club, where there's lots of music, lots of distractions.”

Dr Sadie Boniface, Head of Research at the Institute of Alcohol Studies told Full Fact that adding more alcohol, such as a shot of vodka, “would not necessarily have any of the effects shown in the poster” and that  “adding more alcohol to someone’s drink without their knowledge or permission still counts as spiking”.

How common is spiking?

The National Police Chiefs’ Council has said that it is difficult to get a true picture of the prevalence of drink spiking due to poor data, and that existing figures were likely to be significant underestimates.

A YouGov poll conducted in October 2021 found that 11% of women and 6% of men said they had had a drink spiked.

Image courtesy of tookapic