Officers are investigating after a 32-year-old woman who had been socialising in a pub in the George's Street area on Saturday night noticed two dissoluble tablets in a shot glass from which she had drunk.
The incident happened at around 1.15am after the woman had a Jagermeister.
She later went back to her south inner city apartment and was sick before recovering.
Gardai were alerted and the matter is now being investigated by officers at Pearse Street station.
"Thankfully this is a rare occurrence in Ireland, but people who are out socialising should be careful of anyone putting tablets in their drinks," a source said.
The Rape Crisis Network Ireland has regularly warned of the risks associated with alcohol consumption, and told people to be on their guard for spiked drinks.
Most cases of spiking occur with the intention of sexual assault or robbery.
The majority of cases occur in nightclubs and bars and at parties.
Dizziness, blackouts, poor coordination and decreased inhibitions are a few of the effects.
Source: Ken Foy, Irish Independent, 20/11/14