GI upset
Most toxins will cause gastrointestinal irritation that later leads to nausea, vomiting, and even diarrhea.
If that happens to dogs, then they will instantly lose their appetites before other signs set in. In some instances, if the pet starts vomiting, you might even notice blood. Vomiting is one of the first signs of drug ingestion, poisonous plant ingestion, and toxic food ingestion.
If your dog starts vomiting, you shouldn’t ignore it. Make sure you look for evidence of toxic ingestion, and then contact your vet.
Lethargy
Toxins might adversely mess up your organs and body functions, which causes a dog to feel sick and uncomfortable.
Lots of dogs are tired and lethargic when they don’t feel well. Besides, some toxins, such as rat poison, might cause internal bleeding.
This blood loss might eventually lead to lethargy. Xylitol, a well-known artificial sweetener, might cause low blood sugar, which might cause lethargy in pets.