Simon James Hickey (44), of Petite Route des Mielles, was fined a total of £550 after he admitted possession of cocaine, ecstasy and cannabis in the Tenby Bars at St Aubin.
Centenier Amanda Wright said that door staff were carrying out checks in the toilet cubicles of the pub on the night of 12 May.
One of the cubicles was occupied and when a man came out, he was asked if he had been using drugs in the toilets.
He denied doing so and the doorman asked him if he could conduct a search. Hickey reacted by saying there was no need for that and handed over a bag to the doorman.
He then left the pub.
The doorman called the police and went with officers to the nearby Old Court House where they found the defendant.
He admitted possessing 117 mg of cannabis resin, 41 mg of cocaine and one and three quarter ecstasy tablets.
Advocate James Bell, defending, said these were personal amounts and his client had written a letter expressing remorse.
