A woman has invented a napkin that detects when drinks have been spiked.

Danya Sherman is a student at George Washington University. When Sherman was studying abroad, she was drugged and attacked by a friend of hers. She soon realised that she wasn't the only one who had had this experience, so she invented a napkin that could detect 26 of the 40 most common drugs used to spike drinks. The KnoNap works the same way a regular napkin works - except if you dip the corner of the KnoNap into your drink, it'll tell the user whether the likes of Rohypnol, Xanax, Valium, or a host of other common date rape drugs are present. Sherman invented the napkin to "empower" women who may find themselves in similar situations. Her website reads:

"Everyone deserves to know what is in their drink. "(Danya) sought closure by creating a means to empower others to be safer in social settings. Through KnoNap, she is working to combat the rising prevalence of drug-facilitated assault."

The product recently received some funding from Sherman's university and is expected to launch a crowdsourcing campaign later on this year. While preventative measures such as these do not reach the root of the problem - that men should not drug women - being in possession of such a product could make women feel safer if they happen to leave their drinks unattended in bars. A napkin that prevents date rape, like colour changing nail polish and apps that phone the police whenever a user is in danger, will not stop men from sexually assaulting, or drugging, women. To do this, better sex education and consent classes are necessary across the board. But it would still be nice to be able to protect ourselves until that happens.