A German-made wristband capable of testing drinks for “date rape” drugs has sold out after making the media rounds, but have no fear – the 25-year-old creator plans to have another batch ready soon in an effort to combat the growing concern over drinks spiked with certain drugs.

The Xantus Drinkcheck Band is capable of detecting the presence of gamma-hydroxybutyrate (GHB), a drug that is traditionally used in medicines such as anesthesia or to help those suffering from alcohol or opiate withdrawal. Because it is relatively easy and cheap to make, GHB – also known as “liquid ecstasy” or KO drops – is ranked among the four most commonly reported drugs for hospital emergency cases, according to the United Nations. When combined with alcohol, the odorless, colorless, and almost tasteless drug results in drowsiness or memory problems, making it a common factor in drug-related sexual assaults and robberies. 

Kim Eisenmann told the BBC that she was inspired to create the wristband after someone she knew was drugged and assaulted after becoming the victim of a date rape drug.

"This got my partner Sven Hauser and I thinking that date rape drugs are a bad thing, and there must be something to protect yourself," Kim told BBC News. "We started to do some research. We heard about different products but there was nothing that could really help. This is how we started developing this product."

Each bracelet has two single-use test pads and can be kept for up to a year under the right conditions. A user simply needs to stir their drink with a straw and place a few drops on the white band. If the bracelet turns blue after two minutes then the drink has been spiked.

“Xantus is for when you lose sight of your drink or are given someone's drink. In these cases, testing the drink for KO drops can save your health and also your life. The testing of the drinks is based on your personal sense of security because you can now test if you have a bad feeling,” write the creators on their website. 

It joins a growing number of date rape drug-detecting devices. Florida students developed a straw capable of testing for drugs that changes color when it comes into contact with two of the most common date rape drugs, GHB and ketamine. A few years back, North Carolina undergrads tested a nail polish that would similarly change color when it came into contact with GHB and another common date rape drug, rohypnol.

As the company notes, the wristband “does not replace common sense and necessary caution.”