The SPD posted a short PSA this afternoon:

Seattle police are working closely with nightlife owners and staff to address community concerns about drugged drinks at Capitol Hill venues.

At this time, the department has not identified any cases definitively related to drugged drinks or any pattern related to specific nightlife venues, but is actively seeking information about any unreported cases.

Members of the nightlife community have informed SPD that there may be unreported instances of unidentified individuals spiking bar and nightclub patrons’ drinks with incapacitating drugs.

We've been hearing the same concerns. And the problem may be bigger than something bars and the police department alone can fix. On Monday, I put up a Facebook post asking people who believe they've been drugged to report their stories to me. Since then, my phone's been ringing off the hook. We'll have the full story soon.