The Pennsylvania SPCA says the poodle named "Toodles" was rushed to Blue Pearl Emergency Hospital on Monday after being found unresponsive next to its owner.
Police cared for the person while veterinarians cared for the dog.
Officials say after administering Narcan, Toodles became responsive.
Witnesses told officials that the dog owner claimed to share drugs with his dog.
Toodles was given an IV treatment and is expected to make a full recovery.
"Over the course of the last several days, Toodles has miraculously made a full recovery. And, he is just about the sweetest pup around. Everyone loves him. But our hearts still break for all that he has been through. Toodles could have died. He could have had lasting impacts from the drugs that he ingested. But, today he is safe, and he has a new future ahead of him," said the SPCA in a statement.
The condition of Toodles' owner was not immediately known.