My mom's husband takes their dogs out to a concert amplitheater in the suburban bay area to run around and play and stuff. It's a big open space and usually no one is around.
Anyway he was walking them there over the weekend and one of them disappeared for a few minutes but came back fairly quickly. When they got home, the dog that disappeared started acting very strangely. Very paranoid and scared. Didn't appear to recognize my mom or her husband, and was randomly ducking and moving like she was seeing things. She would get bursts of energy and run circles in the yard to a point where they got worried enough to take her to an er vet.
They do some tests and the dog is od'ing on meth and ecstasy. She's severely overheating so the vet sedates her and does what they can. They reach out to the pet poison control board who recommends a certain medicine. After calling around 25 pharmacies my mom finally found one that stocks it in Oakland. They get the meds and it seems to help. She had to stay at the vet for 3 more days.
After they took the dog to the vet, my mom was determined to find where the dog got into these substances so they went back out to amplitheater and after some searching found a homeless encampment hidden away around the same place the dog disappeared.
Pretty scary times, but she appears to be recovering fine.