I used this stuff on Motor this weekend, put it on Saturday morning and he became lethargic several hours later, probably 1 pm or so. I expected slight lethargy per the label (only warning on there) and left him to go to a derby party, expecting to be back several hours later with Adam getting home a little before me. When I got home he was very lethargic, wobbly, stiff legged, and confused. He was having difficultly drinking water and had an accident in the house. He's had maybe 7-8 accidents in his entire life (honestly I thinks it's less) so that's a pretty damn big deal for him. We looked up side effects online and came upon reviews talking about extreme lethargy, wobbliness, confusion, which progressed to seizures in some cases so we immediately washed it off. He developed diarrhea and needed to go out several times throughout the night and Sunday, the lethargy and mild wobbliness persisted throughout the day. He was also very anti-social, which is unusual. This morning he appears to be less lethargic, not wobbly, and is resuming his normal sociability (i.e. Begging and getting under foot while we are cooking), but still appears to have diarrhea.
I spoke with my vet's office this morning and they haven't had any complaints thus far, but will speak with the drug rep about it. I did notice that the problem dogs online appeared to mostly be older dogs or sensitive breeds, so maybe it's safer with younger non-sensitive breeds. Either which way, just a heads up about possible issues.