The arrests, made as part of Operation Citizen, followed multiple searches throughout the city on Friday.
The first major discovery occurred when Gardaí stopped a vehicle on Dublin's southside, uncovering more than 10,000 Zopiclone and Alprazolam tablets with an estimated value of €20,000.
Subsequent raids at a business premises in Ballyfermot and a location in the city centre revealed additional quantities of the same drugs.
In further searches, officers recovered €4,500 in cash along with evidence pointing to a wider drug trafficking operation in Dublin.
A man in his 30s, arrested in connection with the bust, appeared before the Criminal Courts of Justice on Saturday.
A second man, aged in his 50s, is due to appear in Tallaght District Court, facing charges linked to the operation.
