A local newspaper reports that 1-year-old Maddie showed "strong positive cocaine" and active marijuana traces in urine tests conducted this week by an Albuquerque clinic.
A clinic report says veterinarians saw the dog twitching, shaking and walking with poor balance after owner Arlene Saiz brought her in.
The report says because Saiz couldn't pay the vet bill, she signed the dog over to the city Animal Welfare Department.
Saiz says she regrets the decision.
City officials said police found no evidence to file charges against Saiz, who said she doesn't know how the animal consumed the drugs.